i 

# Protocol for the Regulatory Determination 3ii Offic e of Water (4607M) EPA 815 -R- 14

- 005 April 2014 http://water.epa.gov/drink/EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

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### Disclaimer

This document is designed to provide technical background information for the Regulatory Determination 3 (RD 3)

. This document is not a regulation itself, and it does not substitute for the Safe Drinking Water Act (SDWA) or the Environmental Protectio n Ag ency’s (EPA’s) regulations. Mention of trade names or commercial products does not constitute endorsement or recommendation for use.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

ivEPA – OGW DW Protocol for Regulatory Determination 3 April 2014

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## Executive Summary The Safe Drinking Water Act (SDWA), as amended in 1996, requires the Environmental Protection Agency (EPA) to make regulatory determinations every five years on at least five unregulated contaminants. A regulatory determination is a decision about whether or not to begin the process to propose and promulgate a national primary drinking water regulation (N PDWR) for an unregulated contaminant. These unregulated contaminants are chosen from the Contaminant Candidate List (CCL), which SDWA requires the agency to publish every five
years.
In developing CCL 3, EPA improved and built upon the process that was used for CCL 1 and CCL 2. The new CCL 3 process was based on substantial expert input and recommendations from the National Academy of Science’s (NAS) National Research Council (NRC) and the National Drinking Water Advisory Council (NDWAC) as well as input from the public. Based on these consultations and input, EPA developed a multi- step process to select candidates for the final CCL 3 . EPA published the final CCL 3, which listed 116 contaminants, in the FR on October 8, 2009. The contaminants on CCL 3 were evaluated for the third round of regulatory determination (RD 3)

. In 2011, in response to a Government Accountability Office (GAO) report and a Congressional

c ommittee hearing, EPA prepared a first iteration of this report, the October 2011 Draft Protoco l for the Regulatory Determination 3. The draft Protocol described the approach used to select contaminants from the CCL 3 for regulatory determination

. EPA con vened a seven

- member expert panel to conduct an independent, scientific expert review of the agency ’s d raft Protocol

. The goals of the expert review were to ensure that EPA’s protocol adequately addresses the GAO ’s recommendations for improving the consistency, clarity and transparency in the process for identifying unregulated drinking water contaminants that pose the greatest public health concern under the SDWA. EPA subsequently updated the draft Protocol to include input received from the expert review . This document, Protocol for the Regulatory Determination 3 , is the result of that revision. The outside experts’ comments, and EPA’s responses that formed the basis for the revisions, can be found in Response to External Expert Review of the Regulatory Determination 3 Protocol: Expert Review Comments with EPA Responses

.
This d ocument is structured as follows: Section 1 is an introduction that provides an overview of the drinking water program risk management processes. Section 2 presents the background of the CCL and Regulatory Determination processes and the Unregulated Contaminant Monitoring Regulation (UCMR) established under the 1996 SDWA Amendments. Section 3 provides background on the CCLs and Regulatory Determinations that preceded CCL 3. Section 4 includes an in-depth discussion of the approach for and development of CCL 3. Section 5 explains the role of the UCMR and its relationship to the CCL and Regulatory Determination
processes. Section 6 describes EPA’s new Drinking Water Strategy, including provisions to consider regulation of related contaminants as groups rather than individually. Section 7 provides an overview of the Regulatory Determination process and outreach/consultation activities associated with this process. Section 8 explains in detail the RD 3 protocol, the process by which the agency evaluated chemical contaminants from CCL 3 for inclusion in RD 3 and against the three statutory criteria for regulatory determinations. RD 3 involved a three

- phase process: (1)EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

vi the Data Availability Phase, (2) the Data Evaluation Phase, and (3) the Regulatory Determination Assessment Phase.

This document also includes seven appendices that provide additional detailed background information and supporting materials relevant to the implementation of RD 3. These are:

• Appen dix A – Health Reference Levels provides an explanatio n of the health reference level (HRL), its role in the Regulatory Determination process, and how it is derived for carcinogens and non -carcinogens.

• Appendix B – Health Assessment Data Sources for RD 3 explains how health assessments were used for RD 3 and describes the sources of the drinking water health data used by EPA to support regulatory determinations.

• Appendix C – Data Sources for Occurrence describes the data sources EPA used to evaluate occurrence and exposure for contaminants considered for regulatory determinations.

• Appendix D – Summary of Phase 1: Data Availability provides a summary of the outcome of the Phase 1 evaluation of 116 contaminants and includes information about occurrence data type, best available occurrence data source, primary health effects data source, health assessment status, and whether the contaminant was placed on the short list for Phase 2.

• Appendix E – Summary of Phase 2: Data Availability provides a summary of the outcome of the Phase 2 evaluation of 35 contaminants and includes information about contaminant background (e.g., production/release, fate/transport), health effect findings, initial occurrence findings, and the rationale for the outcome of the Phase 2 evaluation.

• Appendix F – Summary of Phase 3: Regulatory Det ermination Assessments provides a summary of the outcome of the Phase 3 evaluation of ten contaminants and includes information about contaminant background, health effect findings, occurrence findings, other relevant information (e.g., sensitive subpopulations, mobility), and conclusions.

• Appendix G - Evaluation of Statutory Criterion #3 : explains the factors the EPA Administrator may consider when determining whether regulation would provide a meaningful opportunity to improve public health.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

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## Contents
Executive Summary ...........................................................................................................................v
Contents .............................................................................................................................................vii

Exhibits ..............................................................................................................................................x

Abbreviations .....................................................................................................................................xii

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

2. The 1996 SDWA Amendments and the CCL and Regulatory Determination Processes ................................................................................................................................2 2.A. The Contaminant Candidate List (CCL) ................................................................................2 2.B. Regulatory Determinations ....................................................................................................2 2.C. The Unregulated Contaminant Monitoring Regulation (UCMR) ..........................................3

3. Regulatory Determination Cycles for CCL ...........................................................................4 3.A. The First Contaminant Candidate List (CCL 1) ....................................................................4 3.B. The Regulatory Determination 1 ...........................................................................................4 3.C. The Second Contaminant Candidate List (CCL 2) ................................................................5 3.D. The Regulatory Determination 2 ...........................................................................................5 3.E. The Regulato ry Determination for Perchlorate ......................................................................6

4. The Third Contaminant Candidate List (CCL 3) ...................................................................6 4.A. The Approach for CCL 3 .......................................................................................................6 4.B. Creating the Universe ............................................................................................................8 Chemical Contaminants .........................................................................................................8 Microbial Contaminants .........................................................................................................8 4.C. Screening to the PCCL ...........................................................................................................9 Chemical Contaminants .........................................................................................................9 Microbial Contaminants .........................................................................................................9 4.D. Arriving at the CCL ...............................................................................................................9 Chemical Contaminants .........................................................................................................9 Microbial Contaminants .........................................................................................................10 4.E. All Contaminants – Nominations, Expert Input, and Public Comment .................................10 4.F. Results of CCL 3 ....................................................................................................................10

5. UCMR and Its Relationship to the Regulatory Development Process ..................................13

6. Drinking Water Strategy ........................................................................................................14

7. EPA’s Regulatory Determination Process .............................................................................15

8. The Regulatory Determination 3 Process ..............................................................................16 8.A. Phase 1: Data Availability ....................................................................................................18 8.A.1. Health Data Availability Assessment .......................................................................19 8.A.1.a. Is a Health Assessment Available or In Process? ....................................19 8.A.2. Occurrence Data Availability Assessment ................................................................20 8.A.2.a. Are Nationally Representative Finished Water Occurrence Data Available? ......................................................................................................20EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

viii 8.A.2.b. Are Non

- National Finished Water Occurrence Data Available that Show Occurrence at Levels of Public Health Concern? ................................20 8.A.3. Evaluation of Outcomes of Health and Occurrence Data Availability Assessments 21 8.A.4. Outcome of Phase 1 for Regulatory Determination 3 ...............................................22 8.B. Phase 2: Data Evaluation .......................................................................................................24 8.B.1. Phase 2

-- Step1: Collect and Evaluate Health Information and Derive a Draft HRL 24 8.B.1.a. Derivation of the Draft H RL and Consideration of Sensitive Populations .....................................................................................................25 8.B.2. Phase 2

-- Step 2: Gather and Evaluate Additional Occurrence Data Sources R elative to the Draft HRL ..........................................................................................26 8.B.3. Phase 2

-- Step 3: Identify Contaminants Occurring at Levels and Frequencies of Public Health Co ncern ...............................................................................................26 8.B.4. Phase 2

-- Step 4: Identify Contaminants That Have No or Low Occurrence at Levels of Public Health Concern ...............................................................................27 8.B.5. Outcome of Phase 2 for Regulatory Determination 3 ...............................................28 8.C. Phase 3: Regulatory Determination Assessment ..................................................................29 8.C.1. Evaluation of Statutory Criterion #1 (Adverse Health Effect) .................................29 8.C.2. Evaluation of Statutory Criterion #2 (Known or Likely Occu rrence in PWSs with a Frequency and Level of Concern) ...........................................................................30 8.C.2.a. Factors of Primary Consideration .............................................................30 8.C.2.b. Additional Factors of Consideration .........................................................30 8.C.3. Evaluation of Statutory Criterion #3 (Meaningful Opportunity) ..............................31 8.C.4. Making a Regulatory Determination Decision .........................................................31 8.C.5. Outcome of the Regulatory Determination Assessment Phase for Regulatory Determination 3 .........................................................................................................33

9. References Cited ....................................................................................................................33 Appendix A. Health Reference Levels ................................................................................37 Unidentified Mode of Action .................................................................................................37 Mutagenic Mode of Action ....................................................................................................37 Appendix B. Health Assessment Data Sources for RD 3 ....................................................40 EPA Health Assessments: ..................................................................................................................40 Non

- EPA Health Assessments: ..........................................................................................................42 Appendix C. Data Sources for Occurrence .........................................................................44 National Da ta Sources (National Drinking Water Data) ...................................................................44 Unregulated Contaminant Monitoring Regulation (UCMR) Assessment Monitoring (AM): .........................................................................................................................44 Unregulated Contaminant Monitoring Regulation: Screening Surveys (SS): .......................45 Unregulated Contaminant Monitoring (UCM): .....................................................................45 National Inorganic and Radionuclide Survey (NIRS): ..........................................................45 Unr egulated Contaminant Monitoring Regulation 1 Screening Survey: ...............................46 Disinfection By

- Product Information Collection Rule (DBP ICR): ......................................46 Individual States’ Data ...........................................................................................................46 Supplemental Drinking Water Data Sources .....................................................................................47 Community Wat er System Survey (CWSS): .........................................................................47EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

ix Consumer Confidence Reports (CCRs): ................................................................................47 Pesticide Data Program (PDP): ..............................................................................................47 United States Geological Survey Pilot Monitoring Program (USGS PMP): .........................47 Environmental Working Group (EWG): ...............................................................................48 Supplemental Ambient/Source Water Data Sources .........................................................................48 USGS National Water Quality Assessment Program (NAWQA): ........................................48 EPA Storage and Retrieval database (STORET): ..................................................................48 USGS National Reconnaissance of Emerging Contaminants (NREC): ................................48 Production/Use/Release Data Sources ...............................................................................................49 Chemical Update System/Inventory Update Rule (CUS IUR): .............................................49 EPA Office of Pesticide Programs (OPP) Reregistration Documents: ..................................49 National Center for Food and Agricultural Policy (NCFAP): ...............................................49 USGS Pesticide Use Maps: ....................................................................................................49 Toxics Release Inventory (TRI ): ...........................................................................................50 Appendix D. Summary of Phase 1: Data Availability .........................................................51 Appendix E. Summary of Phase 2 Data Evaluation ...........................................................51 Appendix F. Summary of Phase 3 Regulatory Determination Assessments ......................51 Appendix G. Evaluation of Statutory Criterion #3 ..............................................................52EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

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### Exhibits
Exhibit 1: Drinking Water Program Risk Management Process es ....................................................1 Exhibit 2: CCL, Regulatory Determination, and UCMR Timeline ...................................................4 Exhibit 3: General Overview of the Approach Used to Establish CCL 3 .........................................8 Exhibit 4: CCL 3 Chemicals and Chemical Groups ..........................................................................11 Exhibit 5: CCL 3 Microbiological Contaminants ..............................................................................13 Exhibit 6: The Three Primary Phases of the Technical Assessment of the Regulatory Determination 3 Process. .......................................................................................................18 Exhibit 7: Contaminants to be Evaluated in Phase 2 of the Regulatory Determination Process .......22 Exhibit 8: Regulatory Determination Outcomes ................................................................................33

Exhibit 1 : Drinking Water Program Risk Management Processes ....................................................1 Exhibit 2: CCL, Regulatory Determination, and UCMR Timeline ...................................................4 Exhibit 3: General Overview of the Approach Used to Establish CCL 3 .........................................8 Exhibit 4: CCL 3 Chemicals and Chemical Groups ..........................................................................11

Exhibit 5: CC L 3 Microbiological Contaminants ..............................................................................13 Exhibit 6: The Three Primary Phases of the Technical Assessment of the Regulatory Determinati on 3 Process. .......................................................................................................18 Exhibit 7: Contaminants to be Evaluated in Phase 2 of the Regulatory Determination Process .......22 Exhibit 8: Regulatory Determination Outcomes ................................................................................33EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

xiEPA – OGW DW Protocol for Regulatory Determination 3 April 2014

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## Abbreviations

ADAF Age Dependent Adjustment Factors
AMS Agricultural Marketing Service
ATSDR Agency for Toxic Substances and Disease Registry
AWWA American Water Works Association
BMDL Benchmark Dose Lower Confidence Limit
BW Body Weight
CASRN Chemical Abstract Services Registry Number
CCL Contaminant Candidate List
CCL 1 First Contaminant Candidate List
CCL 2 Second Contaminant Candidate List
CCL 3 Third Contaminant Candidate List
CCR Consumer Confidence Report
CERCLA Comprehensive Environmental Response, Compensations, and Liability Act of 1980
CSF Cancer Slope Factor
CUSIUR Chemical Update System / Inventory Update Rule
CVOC Carcinogenic Volatile Organic Compound
CW Concentration in Water
CWS Community Water System
CWSS Community Water Systems Survey
DBP Disinfection By

- Products
DBP ICR Disinfection By

- Product Information Collection Rule
DDE 1, 1

- Dichloro

- 2,2

- bis( p

- chlorophenyl)ethylene
DWI Drinking Water Intake
DWS Drinking Water Strategy
EPA Environmental Protection Agency
EPTC s

- Ethyl dipropylthiocarbamate
ESA Acetochlor ethanesulfone acid
EWG Environmental Working Group
FIFRA Federal Insecticide, Fungicide, and Rodenticide Act FQPA Food Quality Protection Act
FR Federal Register
HA Health Advisory
HRL Health Reference Level
IRIS Integrated Risk Information System
LOAEL Lowest

- Observed

- Adverse

- Effect Level
MCL Maximum Contaminant Level
MCLG Maximum Contaminant Level Goal
MOA Mode of Action
MRL Minimum Reporting LimitEPA – OGW DW Protocol for Regulatory Determination 3 April 2014

xiii NAS National Academy of Sciences NAWQA National Water Quality Assessment
NCFAP National Center for Food and Agricultural Policy
NCOD National Contaminant Occurrence Database
NDBA N

- nitroso

- di

- n

- butylamine
NDEA N

- Nitrosodiethylamine
NDMA N- Nitrosodimethylamine
NDPA N

- Nitrosodipropylamine
NDPhA N

- Nitrosodiphenylamine
NDWAC National Drinking Water Advisory Council
NIRS National Inorganics and Radionuclides Survey
NMEA N

- nitrosomethylethylamine
NOAEL No

- Observed

- Adverse

- Effect Level
NPDWR National Primary Drinking Water Regulation
NPYR N

- Nitrosodipyrolidene
NRC National Research Council
NREC United States Geological Survey National Reconnaissance of Emerging Contaminants
OA Acetochlor oxanilic acid
OEHHA Office of Environmental Health Hazard Assessment (California)
OGWDW Office of Ground Water and Drinking Water
OPP Office of Pesticide Programs
OPP IRED Office of Pesticide Programs Interim Reregistration Eligibility Decision
OPP TRED Office of Pesticide Programs Tolerance Reregistration Eligibility Decision
ORD Office of Research and Development
OW Office of Water
PCCL Preliminary Contaminant Candidate List
PDP Pesticide Data Program
PFOA Perfluorooctanoic acid
PFOS Perfluorooctane sulfonic acid
PMP United States Geological Survey Pilot Monitoring Program
PRZM / EXAMS Pesticide Root Zone Model / Exposure Analysis Modeling System
PWS Public Water System
RDX Cyclotrimethylenetrinitramin e RED Reregistration Eligibility Decision
RD 3 Regulatory Determination 3
RfD Reference Dose
RSC Relative Source Contribution
RTEC S Registry of Toxic Effects for Chemical Substances
SAB Science Advisory Board
SCI- GROW Screening Concentrations in Ground Water Model
SDWA Safe Drinking Water Act
STORET Storage and RetrievalEPA – OGW DW Protocol for Regulatory Determination 3 April 2014

xiv TCP 1,2,3

- Trichloropropane
TPTH Triphenyltin hydroxide
TRI Toxics Release Inventory
TSCA Toxic Substances Control Act
UCM Unregulated Contaminant Monitoring
UCMR Unregulated Contaminant Monitoring Regulation
UCMR 1 First Unregulated Contaminant Monitoring Regulation
UCMR 2 Second Unregulated Contaminant Monitoring Regulation
UCMR 3 Third Unregulated Contaminant Monitoring Regulation
UF Uncertainty Factor
USDA United States Department of Agriculture
USGS United States Geological Survey
WBDO Waterborne Disease Outbreak
WHO World Health OrganizationEPA – OGW DW Protocol for Regulatory Determination 3 April 2014

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## 1

. I ntroduction The 1996 Safe Drinking Water Act (SDWA) Amendments required that EPA develop a revised risk management and regulatory development approach for drinking water in order to protect public health. To meet these requirements EPA developed an integrated framework (Exhibit 1)
to:

(1) L ist currently unregu lated contaminants of public health concern, called the Contaminant Candidate List (CCL); (2) E valuate these contaminants and determine whether or not the contaminants warrant a national primary drinking water regulation (NPDWR), called Regulatory Determinati on; (3) C ollect drinking water monitoring data for unregulated contaminants under the Unregulated Contaminant Monitoring Regulation (UCMR); and (4) P eriodically review existing regulations and assess whether revisions are needed that maintain or improve public health protection for drinking water consumers ( called the Six

- Year Review).

Exhibit 1 : Drinking Water Program Risk Management Processes

The purpose of this document is to provide a detailed summary of the protocol used for the third cycle of Regulatory Determination ( i.e., Reg ulatory Det ermination 3 , or RD 3 ) and the evaluation of the unregulated contaminants listed on the third CCL ( CCL 3). In developing CCL 3 and RD 3, EPA has util ized input from peer reviews and expert consultations, including several reports from the National Academy of Sciences’ (NAS’s) National Research Council (NRC), reviews by EPA’s Science Advisory Board (SAB), and the National Drinking Water Advisory Council (NDWAC) , as well as other stakeholder input and public comment. At each stage, need increased specificity and confidence in the type of supporting data used (e.g., health and occurrence). Public consultation is involved in each step of the process.

Draft CCL

Final CCL

Final Rule (NPDWR) Six Year Review of Existing NPDWRs No further action if EPA makes decision to not regulate (may develop health advisory; may consider for future CCL) Preliminary Regulatory Determinations

Final Regulatory Determinations Proposed Rule (NPDWR) Draft UCMR

Final UCMR

UCMR Monitoring ResultsEPA – OGW DW Protocol for Regulatory Determination 3 April 2014

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## 2. The 1996 SDWA Amendments and the CCL and Regulatory Determination Processes As noted, the 1996 SDWA Amendments direct EPA to periodically publish a list of unregulated contaminants that may pose risks to public health from drinking water (the CCL) and to periodically make determinations on whether or not to regulate any CCL contam inant with a n NPDWR

. The specific statutory requirements for the CCL and Regulatory D eterminations can be found in SDWA Section 1412(b)(1). The statutory requirements for a related effort, the UCMR can be found in SDWA Section 1445(a)(2).



### 2.A. The Contamin ant Candidate List (CCL) The 1996 SDWA Amendments required EPA to publish the first CCL (CCL 1) by February 1998, 18 months after the date of enactment , and to publish a new CCL every 5 years thereafter. The CCL is a list of contaminants that are not subje ct to any proposed or promulgated NPDWRs, are known or anticipated to occur in public water systems (PWSs), and may require regulation under SDWA to protect public health. SDWA also specifie s that the CCL must consider substances identified in section 101( 14) of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) and substances registered as pesticides under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), and must consider data and information from the National Contaminant Occurrence Database (NCOD), which EPA established as required under SDWA S ection 1445(g). For the CCL, SDWA requires consultation with the scientific community, including EPA’s Science Advisory Board, and opportunity for public comment. The CCL is the starting point for the Regulatory Determination process and is the list of priority contaminants that are evaluated for potential drinking water regulations.



### 2.B. Regulatory Determinations The 1996 SDWA Amendments , section 1412(b)(1)(A), direct EPA to determine whether or not to regulate at least five contaminants from the most recent CCL every five years and allow an opportunity for public notice and comment. The first Regulatory Determination was due within three and one

- half years afte r the publication of CCL 1, and then every five years thereafter. When making a regulatory determination, the 1996 SDWA Amendments require that EPA assess three criteria and decide whether :

(1) The contaminant may have an adverse effect on the health of persons. (2) The contaminant is known to occur or there is substantial likelihood that the contaminant will occur in PWSs with a frequency and at levels of public health

concern

. (3) In the sole judgment of the Administrator, regulation of such contaminant presents a meaningful opportunity for health risk reduction for persons served by PWSs.

If EPA finds that all three of these statutory criteria are met , it makes a determination to regulate the contaminant (i.e., a positive determination)

. Following a positive regulatory determination,EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

3 the agency has 24 months to publ ish a proposed M aximum Contaminant L evel G oal (MCLG) 1
and NPDWR 2 . After the proposal, the agency has 18 months to publish a final MCLG and promulgate a final NPDWR (SDWA section 1412(b)(1)(E)). 3 If EPA finds that one or more of these statutory criteria are not met, it makes a determination not to regulate the contaminant (i.e., a negative determination)

. A determinati on not to regulate a contaminant is considered a final agency action and is subject to judicial review.



### 2.C. The Unregulated Contaminant Monitoring Regulation (UCMR) The 1996 SDWA Amendments (section 1445(a)(2)) also required that once every five years, beginning in August 1999, EPA issue a new list of no more than 30 unregulated contaminants to be monitored by PWSs. The UCMR occurrence data are designed to help determine if the contaminant occurs “with a frequency and at levels of public health concern” (p er the second statutory criterion for regulatory determinations, above) to support the Administrator’s determination under the Regulatory Determination process of whether or not to regulate a contaminant. The 1996 SDWA Amendments require EPA to enter the monitoring data into a national drinking water contaminant occurrence database (implemented as NCOD)

.
The CCL and UCMR are integral components of the coordinated risk management process that inform and support Regulatory Determination (Exhibit 2 illustrates the time

- line relationship among the programs). The UCMR list of contaminants for each monitoring cycle are developed in coordination with the CCL process. The programs continually support and inform each other. T he UCMR is designed to inform Regulatory Determination, and in some cases may also collect data that would support regulation development and help determine whether new or emerging contaminants should be listed on future CCL s.

1 An MCLG is the maximum level of a contaminant in drinking water at which no known or anticipated adverse effect on the health of persons would occur, and which allows an adequate margin of safety. Maximum contaminant level goals are nonenforceable health goals.
2 An NPDWR is a legally enforceable standard that applies to PWSs. An NPDWR sets a legal limit (called a maximum contaminant level or MCL) or specifies a certain treatment technique (TT) for public water systems for a specific contaminant or group of contam inants.
3 The statute authorizes a nine

- month extension of this promulgation date.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

4 Exhibit 2 : CCL, Regul atory Determination, and UCMR Timeline



## 3. Regulatory Determination Cycles for CCL

3.A. The First Contaminant Candidate List (CCL 1) The 1996 SDWA Amendments required EPA to publish the first CCL (CCL 1) 18 months after the date of enactment. Following the 1996 SDWA Amendments, EPA sought input from the NDWAC on the process that should be used to identify contaminants for inclusion on the CCL. For chemical contaminants, the agency developed screening and evaluation criteria based on recommendations from N DWAC. For microbiological contaminants, NDWAC recommended that the a gency seek external expertise to identify and select potential waterborne pathogens. As a result, the agency convened an international panel of microbiologists and public health experts wh o developed criteria for screening and evaluation, and subsequently developed an initial list of potential microbiological contaminants.

Within the short time frame required by SDWA, EPA developed the first CCL based largely on expert knowledge and the evaluation of readily available information. EPA receive d benefi cial input from the NDWAC, the scientific community, and the public (through stakeholder meetings and the public comments ). EPA published the draft and final CCL 1 in the Federal Register on October 6, 1997 (62 FR 52193; USEPA, 1997) and March 2, 1998 (63 FR 10273 ; USEPA, 1998) , respectively

. The final CCL 1 contained 50 chemical and 10 microbiological contaminants.



### 3.B. The Regulatory Determination 1 EPA published the preliminary and final r egulatory determinations for 9 CCL 1 contaminants in the Federal Register on June 3, 2002 (67 FR 38222 ; USEPA, 2002 ) and July 18, 2003 (68 FR 42898; USEPA, 2003) , respectively

. EPA determined that 9 of the 60 CCL 1 contaminants had sufficient data and info rmation available to make regulatory determinations. The nine contaminants were Acanthamoeba , aldrin, dieldrin, hexachlorobutadiene, manganese, 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016

Reg ulatory
Det ermination 1 : 9 Contaminants Reg ulatory
Det ermination 2 : 11 Contaminants Reg ulatory
Det ermination 3

UCMR 1 : 25 Contaminants ( Monitoring 2001

- 2003) UCMR 2 : 25 Contaminants (Monitoring 200 8

- 20 1 0) UCMR 3 : 30 Contaminants (Monitoring 2013

- 2015) CCL 1: 60 Contaminants CCL 2: 51 Contaminants CCL 3: 11 6 ContaminantsEPA – OGW DW Protocol for Regulatory Determination 3   April 2014

5 metribuzin, naphthalene, sodium, and sulfate. The agency decided not to regulate any of these nine contaminants due to no or low occurrence in PWSs and/or no meaningful opportunity to protect public health. The agency posted information about Acanthamoeba 2 on the EPA website and issued health advisories for manganese, sodium, and sulfate (available at http://water.e pa.gov/drink/standards/hascience.cfm).

The decision -making process that EPA used to make its regulatory determinations for CCL 1 was based on expert input and recommendations from different groups including the NRC, NDWAC , and stakeholders. In June 2002, EPA consulted with the Science Advisory Board (SAB) Drinking Water Committee on whether the protocol EPA developed, based on the NDWAC recommendations, was consistently applied and appropriately documented. SAB provided verbal feedback and recommended that the a gency provide a transparent and clear explanation of the process for making regulatory determinations. The agency took SAB’ s recommendation into consideration and further explained the CCL 1 regulatory determination evaluation process in the July 18, 2003 (68 FR 42898; USEPA, 2003) notice and in the supporting documentation (see also 67 FR 38222 ; USEPA, 2002 ).



### 3.C. The Second Contaminant Candidate List (CCL 2) After completing CCL 1, the agency began the process to develop an enhanced, more robust approach to evaluating the risk of potential drinking water contaminants for future CCLs. The
agency asked the National Academy of Sciences’ NRC for guidance on a more rigorous and expansive approach for the CCL ( see section 4 ). Since NRC’s evaluation overlapped with the statutory timeline for developing the second CCL (CCL 2), the agency continued to develop the more rigorous CCL process while simultaneously publish ing a CCL 2 that carried forward the 51 contaminants remain ing on CCL 1 . The agency publishe d its draft and final CCL 2 in the Federal Register on April 2, 2004 (69 FR 17406 ; USEPA, 2004 ) and February 24, 2005 (70 FR 9071; USEPA, 2005a) , respectively

.


### 3.D. The Regulatory Determination 2 EPA used the same approach for Regulatory Determination 2 as was used for evaluating whether
or not to regulate contaminants for Reg ulatory Det ermination 1. The agency published its preliminary and final regulatory determinations for 11 CCL 2 contaminants in the Federal Register on May 1, 2007 (72 FR 24106; USEPA, 2007a) and July 30, 2008 (73 FR 44251; USEPA, 2008a) , respectively . EPA determined that 11 of the 51 CCL 2 contaminants had sufficient data and information available to make regulatory determinations. The 11 contaminants were boron, the dacthal mono- and di-acid degradates, 1,1- dichloro -2,2- bis(p

chlorophenyl)ethylene (DDE), 1,3 -dichloropropene, 2,4-dinitrotoluene, 2,6-dinitrotoluene, sethyl dipropylthiocarbamate (EPTC), fonofos, terbacil, and 1,1,2,2- tetrachloroethane. The agency decided not to regulate any of these 11 contaminants due to no or low occurrence in PWSs and/or no meaningful opportunity for public health protection. The agency did, however, issue health advisories for boron, dacthal degradates , 2,4- dinitrotoluene, 2,6 -dinitrotoluene and 1,1,2,2- tetrachloroethane (available at http://water.epa.gov/drink/standards/hascience.cfm).

2 Consumer information about Acanthamoeba for people who wear contact lenses can be found at http://water.epa.gov/action/advisories/acanthamoeba/index.cfmEPA – OGW DW Protocol for Regulatory Determination 3 April 2014

6 

### 3.E. The Regulatory Determination for Perchlorate EPA published a preliminary determin ation not to regulate perchlorate with a national primary drinking water regulation in October 2008 (73 FR 60262; USEPA, 2008b). In 2009, EPA solicited input from the public on approaches for analyzing and evaluating perchlorate data (74 FR 41883; USEPA, 2009a and 74 FR 48541; USPEA, 2009b), and in February 2011, EPA issued a final determination to regulate perchlorate (76 FR 7762; USEPA, 2011a). This decision is the first time EPA has decided to regulate a substance from the CCL.

E PA d etermined that perchlorate met SDWA’s three criter ia for regulating a contaminant:

(1) Perchlorate may have adverse health effects because scientific research indicates t hat perchlorate can disrupt the thyroid’s ability to produce hormones needed for normal growth and development (which could be of special concern for fetuses, newborns, and children)

. (2) There is a substantial likelihood that perchlorate occurs with frequency at levels of health concern in public water systems because monitoring data show over four percent of public water systems have detected perchlorate

. (3) There is a meaningful opportunity for health risk reduction for the 5.2 to 16.6 million people who may be served drinking water containing perchlorate.

The agency is currently developing the proposed drinking water regulation for perchlorate.



## 4. The Third Contaminant Candidat e List (CCL 3)

4.A. The Approach for CCL 3 In developing CCL 3, EPA improved upon the process that was used to develop CCL 1 and CCL 2. This new process was based on substantial expert input and recommendations from the NRC, NDWAC and input from the public.

The NRC recommended a multi-step process including using a prototype classification algorithm that evaluates attributes in conjunction with expert judgment to identify contaminants for future CCLs. The approach is based on predictive features or attributes that characterize the occurrence in drinking water and health effects of each contaminant. The NRC described two health effects attributes and three occurrence attributes. The health effects attributes are severity and potency, and the occurrence attributes are prevale nce, magnitude, and persistence/ mobility (used as a surrogate for prevalence when a contaminant had no occurrence data).

The details of the NAS

- NRC recommendation s are available in the report entitled “Classifying Drinking Water Contaminants for Regulatory Considerations ” (NAS , 2001). It is important to emphasize that the NRC report only gives a broad framework for EPA to develop its own prototype classification scheme and then to calibrate the scheme using diagnostic contaminants.

W ith the NAS

- NRC recommendations in hand, the Office of Water turned to the NDWAC to provide advice on how to implement the approach recommended in the NAS- NRC report. The NDWAC formed a subcommittee to provide advice to the NDWAC and then to EPA.

Based on the deliberations of the NDWAC Work Group, NDWAC released a report in May 2004 and noted that EPA may need several CCL cycles to fully develop and implement the NRCEPA – OGW DW Protocol for Regulatory Determination 3 April 2014

7 recommended approach (NDWAC , 2004). While the NDWAC agreed with the overall approach, the group noted that not all the data and information needed to develop the NRC-envisioned CCL we re available at th e time. The NDWAC al so recognized that the CCL process could be refined and improved in successive efforts; therefore, the agency should take advantage of the knowledge gained and improve upon the next CCL using an adaptive management approach.

Based on these consultations with expert groups and stakeholders, EPA developed a multi- step approach to select contaminants for the CCL 3, which includes the following key steps:

(1) Identify a broad universe of potential drinking water contaminants (the CCL 3 Universe). (2) Screen the CCL 3 Universe to develop a preliminary CCL (PCCL) based on the potential of contaminants to occur in public water systems and the potential for public health concern. (3) F urther evaluate the PCCL contaminants based on a more detailed review of occurrence and health effects data to generate the final CCL 3.

Exhibit 3 illustrates the three -step process used to evaluate contaminants for CCL 3.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

8 Exhibit 3 : General Overview of the Approach Used to Establish CCL 3



### 4.B. Creating the Universe

Chemical Contaminants To populate the CCL 3 Universe of Chemicals

, an extensive preliminary list (a “pre -universe”) of approximately 26,000 substances was compiled fro m a wide variety of data sources that met specific criteria

. The preliminary list was refined by focusing on those substances that had some health effects and occurrence information and removing chemicals that are currently regulated in drinking water and substances that are considered mixture s of chemicals . The public also had an opportunity to nominate chemicals to the Universe of Chemicals. The resultant CCL 3 Universe included approximately 6,000 chemic als (for further details, see USEPA, 2009c).

Microbial Contaminants To assemble the CCL 3 Universe of microbiological contaminants, EPA reviewed the literature and compiled a list of known human pathogens. As a result of the literature review and public nominations process, the Universe included a total of 1,425 pathogens (for further details, see USEPA, 2009 d ). Classification Tools

Evaluation

Expert Review

Universe

PCCL

Proposed CCL Surveillance

and

Nomination STEP 1

Identify the

STEP 2

Screen

to a PCCL

STEP 3

Select the CCL

Final CCLEPA – OGW DW Protocol for Regulatory Determination 3 April 2014

9 

### 4.C. Screening to the PCCL

Chemical Contaminants The chemicals in the CCL 3 Universe were then screened using a framework that took into account bo th health effects and occurrence data. In the case of health effects, EPA evaluated both quantitative and qualitative information on the hazard and/or dose-response properties of the contaminants. For occurrence, EPA evaluated both quantitative and qualita tive information on occurrence in water, releases to the environment, and amounts produced.

EPA categorized contaminants according to their potential to occur in PWS s and their potential for public health concern. For occurrence, c ategories were developed for each available data source to evaluate the potential occurrence in PWSs. For public health concern, c ategories were developed for each available toxicity parameter . To be most protective of public health, chemicals that had health effects properties t hat placed them in the highest toxicity category were moved forward for further evaluation, even if their occurrence was limited. And because of their health concerns and obvious exposure potential, known disinfection by- products (DBPs) were considered to have “default” occurrence potential even if no actual occurrence information was available , and they were also moved forward for further review. As the result of this screening process, 561 chemical contaminants from the approximately 6,000 chemicals in th e CCL 3 Universe were selected to move on to the Preliminary CCL 3 (PCCL 3) (see USEPA, 2009e, for details on the screening process).

Microbial Contaminants EPA developed a set of 12 screening criteria to reduce the Universe of human pathogens to just those pathogens that could cause drinking water- related diseases resulting from ingestion of, inhalation of, or dermal contact with drinking water in the United States. For example, pathogens transmitted solely by animal vectors, pathogens not endemic to North America, and pathogens with a life

- cycle incompatible with drinking

- water transmission were screened out and not included on the PCCL. Based upon this screening exercise, 1,396 of the 1,425 pathogens were excluded and 29 pathogens moved on to the PCCL. (For more information about the screening process for microbial contaminants, see USEPA, 2009 f.)



### 4.D. Arriving at the CCL

Chemical Contaminants To select chemical contaminants for the CCL 3 from among the 561 PCCL contaminants, EPA used classification mo dels as a support tool to handle larger, more complex assortments of data in a consistent and reproducible manner. Classification models are algorithms that use statistical approaches for pattern recognition and derive mathematical relationships among inpu t variables (measurements or descriptive data) and output from a data set used to train the classification model. The classification models were trained by first evaluating chemicals for which regulatory decisions had already been made and for which consid erable occurrence and health effects information was available. A scaling system was developed for four attributes: severity, potency, magnitude, and prevalence (see USEPA, 2009g , for details). Contaminants were scored in eachEPA – OGW DW Protocol for Regulatory Determination 3 April 2014

10 of these attributes, the results were run through three calibrated models, and EPA made several post-model ing refinements to compile the draft list of CCL 3 contaminants. One important refinement was the calculation of ratios comparing health reference levels 3 ( HRLs ) with observed or projected concentrations in water. For listing on CCL 3 , EPA gave precedence to those contaminants with lower ratios (i.e., higher known or anticipated occurrence relative to levels of health concern). See Appendix A for more information on HRLs.

Microbial Contaminants EPA developed a scoring system to assign a numerical value to each pathogen on the PCCL. Each of the pathogens on the PCCL was scored using three scoring protocols, one protocol each for (a) waterborne disease outbreaks (WBDO), (b) occurrence in drinking water and other kinds of water (e.g., recreational, ground water, surface water), and (c) health effects. The higher of the WBDO score or the occurrence score was added to the normalized health effects score to produce a composite pathogen sco re. (For details about the three protocols used to score the pathogens on the PCCL and the process by which the scores were combined, see USEPA, 2009h.)

To determine which of the 29 PCCL pathogens should be included on the draft CCL 3, the agency considered various factors, including the PCCL scores for WBDO, occurrence, and health effects.



### 4.E. All Contaminants – Nominations, Expert Input, and Public Comment EPA also put out a special call for nominations to the CCL 3 (USEPA, 2009i), held expert panel

co nsultations, consulted with the SAB, had the draft list reviewed by a peer review panel, and accepted public comments (USEPA, 2009j) on the draft CCL 3, published on February 21, 2008 (73 FR 9628; USEPA, 2008c).



### 4.F. Results of CCL 3 The final CCL 3 was published on October 8, 2009 (74 FR 51850; USEPA, 2009k). It consists of 104 chemicals or chemical groups (see Exhibit 4) and 12 microbiological contaminants (Exhibit 5). These 116 contaminants serve as the starting point to the R D 3 process and the occurr ence and health- data -driven approach of the CCL 3 process provides a narrowed list of priority contaminants for a focused and more detailed data evaluation for RD 3.

3 The CCL 3 HRL is a risk

- derived concentration developed during the CCL 3 process. The CCL 3 HRLs could be developed using an RfD and/or cancer slope factor from a peer

- reviewed health assessme nt or a published scientific study.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

11 Exhibit 4 : CCL 3 Chemicals and Chemical Groups
Contaminant CASRN Contaminant CASRN

1,1,1,2

- Tetrachloroethane 630206 Halon 1011 (bromochloromethane) 74975

1,1

- Dichloroethane 75343 HCFC

- 22 75456

1,2,3

- Trichloropropane 96184 Hexane 110543

1,3

- Butadiene 106990 Hydrazine 302012

1,3

- Dinitrobenzene 99650 Mestranol 72333

1,4

- Dioxane 123911 Methamidophos 10265926

17alpha

- estradiol 57910 Methanol 67561

1

- Butanol 71363 Methyl bromide (Bromomethane) 74839

2

- Methoxyethanol 109864 Methyl tert

- butyl ether 1634044

2

- Propen

- 1

- ol 107186 Metolachlor 51218452

3

- Hydroxycarbofuran 16655826 Metolachlor ESA 171118095

4,4'

- Methylenedianiline 101779 Metolachlor OA 152019733

Acephate 30560191 Molinate 2212671

Acetaldehyde 75070 Molybdenum 7439987

Acetamide 60355 Nitrobenzene 98953

Acetochlor 60355 Nitroglycerin 55630

Acetochlor ethanesulfonic acid (ESA) 187022113 N

- Methyl

- 2

- pyrrolidone 872504

Acetochlor oxanilic acid (OA) 1 9 4992444 N

- Nitrosodiethylamine (NDEA) 55185

Acrolein 107028 N

- Nitrosodimethylamine (NDMA) 62759

Alachlor ESA 142363539 N

- Nitrosodipropylamine (NDPA) 621647

Alachlor OA 171262172 N

- Nitrosodiphenylamine (NDPhA) 86306

alpha

- Hexachlorocyclohexane 319846 N

- Nitrosodipyrrolidine (NPYR) 930552

Aniline 62533 Norethindrone (19

- Norethisterone) 68224

Bensulide 741582 n

- Propylbenzene 103651

Benzyl chloride 100447 o

- Toluidine 95534EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

12 Contaminant CASRN Contaminant CASRN

Butylated hydroxyanisole 25013165 Oxirane, methyl

- 75569

Captan 133062 Oxydemeton

- methyl 301122

Chlorate 14866683 Oxyfluorfen 42874033

Chloromethane (Methyl chloride) 74873 Perchlorate 14797730

Clethodim 110429624 Perfluorooctane sulfonic acid (PFOS) 1763231

Cobalt 7440484 Perfluorooctanoic acid (PFOA) 335671

Cumene hydroperoxide 80159 Permethrin 52645531

Cyanotoxins (microcystin,

anatoxin

- a, cylindrospermopsin) 64285069, 143545908, 101043372 Profenofos 41198087

Dicrotophos 141662 Quinoline 91225

Dimethipin 55290647 RDX 121824

Dimethoate 60515 sec

- Butylbenzene 135988

Disulfoton 298044 Strontium 7440246

Diuron 330541 Tebuconazole 107534963

Equilenin 517099 Tebufenozide 112410238

Equilin 474862 Tellurium 13494809

Erythromycin 114078 Terbufos 13071799

Estradiol (17

- beta estradiol) 50282 Terbufos Sulfone 56070167

Estriol 50271 Thiodicarb 59669260

Estrone 53167 Thiophanate

- methyl 23564058

Ethinyl Estradiol (17

- alpha ethynyl estradiol) 57636 Toluene diisocyanate 26471625

Ethoprop 13194484 Tribufos 78488

Ethylene glycol 107211 Triethylamine 121448

Ethylene oxide 75218 Triphenyltin hydroxide (TPTH) 76879EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

13 Contaminant CASRN Contaminant CASRN

Ethylene thiourea 96457 Urethane 51796

Fenamiphos 22224926 Vanadium 7440622

Formaldehyde 50000 Vinclozolin 50471448

Germanium 7440564 Ziram 137304

Exhibit 5 : CCL 3 Microbiological Contaminants
Contaminant Contaminant

Adenovirus Hepatitis A virus

Caliciviruses Legionella pneumophila

Campylobacter jejuni Mycobacterium avium

Enterovirus Naegleria fowleri

Escherichia coli (0157) Salmonella enteric a

Helicobacter pylori Shigella sonnei



## 5. UCMR and Its R elationship to the Reg ulatory De velopmen t Process The UCMR is EPA’s primary authority for collecting monitoring data on the occurrence of unregulated contaminants in drinking water

. The UCMR is designed to collect nationally representative occurrence data for a list of contaminants that is developed in coo rdination with the CCL and Regulatory Determination process es

. UCMR is limited by statute to 30 unregulated contaminants during any 5- year cycle ( SDWA section 1445(a)(2)). Large and very large PWSs (those serving between 10,001 and 100,000 people, and those serving over 100,000 people, respectively) are required to handle the sampling and lab oratory analysis and then report the data through EPA ’s electronic reporting system

. EPA coordinates and pays for the shipping and laboratory analysis for a random samp le of small systems (those serving 10,000 or fewer people). EPA published the first list for the Unregulated Contaminant Monitoring Regulation cycle (i.e., UCMR 1) in the Federal Register on September 17, 1999 (64 FR 50556; USEPA, 1999a), with monitoring conducted during 2001-2003. UCMR 2 was published on January 4, 2007 (72 FR 367; USEPA, 2007b), with monitoring conducted during 2008-2010. Monitoring under the third UCMR (UCMR 3) is scheduled to be conducted during 2013-2015. (The monitoring lists are

ava ilable at: http://water.epa.gov/lawsregs/rulesregs/sdwa/ucmr/ .)

The UCMR program was designed using a three -tiered approach for monitoring contaminants based on the availability of analytic al methods. Assessment Monitoring

, applied to List 1EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

14 contaminants, typically relies on analytical methods that are in common use in drinking water laboratories. The Screening Survey, for List 2 contaminants , uses newly developed analytical methods that are not as commonly employed in drinking water laboratories. The Screening Survey involves a smaller number of PWSs due to expectations of reduced laboratory capacity. Pre

- Screen Testing

, for List 3 contaminants, is designed to address contaminants that requi re highly specialized analytical methods , or methods that are in the early stage of development. Pre

Screen Testing will typically involve only a limited number of systems determined to be most vulnerable to the targeted contaminants.

EPA designed the Asse ssment Monitoring sampling frame to ensure that sample results would yield a high level of confidence and a low margin of error (see USEPA, 1999b and 2001, for UCMR design details). Assessment Monitoring is required for all large and very large PWSs (i.e., a census of these systems) and a statistically representative national sample of 800 small PWSs.

Under UCMR 1, the Screening Survey monitoring was conducted by a statistically selected sample of 300 large and small PWSs. While the statistical design provided national data, for rela tively low occurrence contaminants there was concern that there was too much uncertainty in the results to extrapolate results for national estimates

. For the UCMR 2 Screening Survey, the design was improved to include a ce nsus of all very large systems and a statistical sample of 320 large PWSs and 480 small PWSs (72 FR 367; USEPA 2007b). With this larger Screening Survey sample size, sufficient data were generated to provide a national estimate of population exposure.

Under UCMR 1 and UCMR 2, for a variety of reasons that includ ed method availability, laboratory capacity, and contaminant priorities, EPA elected not to specify Pre

- Screen Testing under List 3.

The national design, statistical sampling frame, all new analytica l methods, and the data analysis approach for the UCMR program have been peer reviewed (USEPA , 2001 ; USEPA , 2008d). Details about the sampling frame for small systems can be found in the original UCMR 1 Rule (64 FR 50556; USEPA, 1999a) and an associated support document (USEPA, 1999c). The data collected through the UCMR program are stored in NCOD to facilitate analysis and review of contaminant occurrence, inform the development of the CC L, help EPA to determine if monitored contaminants occur at frequenci es and concentrations that would be of public health

concern under the Regulatory Determination process, and support the development of regulations. For more information about the UCMR program, including monitoring lists and the results of UCMR 1 and UCMR 2 monitoring , see http://water.epa.gov/lawsregs/rulesregs/sdwa/ucmr/

. 

## 6. Drinking Water Strategy In March 2010, EPA announced the a gency’s new Drinking Water Strategy (DWS)

, which aims
to find ways to strengthen public health protection from contaminants in drinking water. The

new strategy is intended to streamline decision making and expand protection under existing laws and promote cost

- effective new technologies to meet the needs of rural , urban and other
water

- stressed communities. The four principles underlying the DWS are:EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

15 (1) Address contaminants as groups rather than one at a time

. (2) Foster development of new drinking water technologies to address health risks posed by a broad array of contaminants. (3) Use the authority of multiple statutes to help protect drinking water

. (4) Partner with states to develop shared access to all PWS monitoring data.

Only the first principle of the DWS (i.e., addressing contaminants as groups) has a direct bearing on regulatory determinations. The agency identified several factors to evaluate which contaminants might be addressed effectively as a group. These factors include whether the contaminants in the group: (a) have a similar health endpo int, (b) can be measured by the same analytical methods, (c) can be treated using the same technolog ies or treatment technique s, and/or (d) have been shown to occur individually and, if data are available, have been shown to occur together . EPA conducted e xtensive national outreach to solicit input from stakeholders on the DWS and how best to address groups of contaminants. Stakeholders generally agreed that these were the more important factors to consider in evaluating contaminants for a group regulation.

The purpose of grouping contaminants by a similar health endpoint is to better protect public health from the potential risk of co -occurring contaminants with common additive or synergistic (i.e., greater than additive) adverse health effects

. The affect ed target organ(s), specific endpoint(s), mechanism(s)/mode(s) of action, functional molecular group(s) and the potential for additive risk based on available data are considered in the selection of endpoints that are used to group contaminants for regulatory consideration. The ability to measure a group of contaminants by the same analytical method and to treat the contaminants using the same technology or treatment technique approach improves cost effectiveness and efficiency of regulating the group of contaminants because there is likely a marginal additional cost for monitoring and/or treating additional contaminants in the group, if they co-occur.

The agency’s decisions regarding groups o f contaminants are important to consider during the RD 3 process . In February 2011, the agency decided to address carcinogenic volatile organic compounds (CVOCs) as a group, which include several CVOCs on CCL 3 (e.g., 1,2,3- trichloropropane, nitrobenzene ). The agency decided to move ahead with a CVOC regulation so any regulatory determinations for CVOCs listed on CCL 3 will be handled with the CVOC regulatory effort. Information about the DWS, including a timeline of decisions and summaries of DWS

- related l istening sessions and stakeholder meetings, is on EPA’s website at: http://water.epa.gov/lawsregs/rulesregs/sdwa/dwstrategy/index.cfm

. 

## 7. EPA’s Regulatory Determination Proce ss The Regulatory Determination p rocess is not a rulemaking but require s public notice (i.e., a Federal Register notice) and an opportunity for public comment, as specified in the 1996 SDWA Amendments. The Regulatory Determination p rocess is distinct from the more detailed analyses needed to develop an NPDWR. Thus, a determination to regulate a contaminant is the beginning of the agency regulatory development process, not the end.

In developing RD 3, EPA’s OGWDW established a formal workgroup to bring together experts from across the agency to share expertise, data, information, and perspectives on the contaminants of interest, and most importantly, to provide review of the quality of the data usedEPA – OGW DW Protocol for Regulatory Determination 3 April 2014

16 and the analyses conducted. The agency workgroup uses the be st available peer

- reviewed data and analyses to conduct its evaluation. The workgroup reviews the details of the technical approach (discussed in section 8 below) and works to develop recommendations for senior
managers.
EPA has presented information on th e Regulatory Determination process at two major public meetings: the Environmental Justice Considerations for Drinking Water Regulatory Efforts, on March 3, 2011, and the Regulatory Determination 3 Public Meeting, on June 16, 2011 (USEPA, 2011b). The agency has also engaged stakeholders and experts throughout the RD 3 process, giving presentations to explain the process and discuss the available data under consideration to various drinking water organizations (e.g., the Association of State Drinking Water A dministrators, the National Drinking Water Advisory Council, and the American Water Works Association ). Any key insights or new data or information identified by stakeholders are also considered in the a gency’s deliberative process.

At a Senate committee h earing on July 12, 2011, in response to a report by the General Accounting Office (GAO) ( GAO , 2011), EPA Deputy Administrator Rob ert Perciasepe made a commitment to improve the transparency of the Regulatory Determination process. The result was a first iteration of this Protocol document, which explains the process that EPA used to make decisions under RD 3. The draft Protocol was reviewed by a panel of seven outside experts on October 26 and 27, 2011 . The panel of experts made a n umber of helpful suggestions for clarification and transparency (USEPA 2011 c). The present Protocol document has been revised in response to feedback from the expert panel. The questions posed to the panel of experts, their responses, and EPA’s acknowledgement of those responses and explanations of how it has acted on them, are contained in a companion comment-response document (USEPA, 2013 ).

The Administrator makes the preliminary and final Regulatory Determination decisions. The preliminary Regulatory Det ermination, positives and negatives, are announced in the Federal Register

. EPA then accepts, reviews, and responds to comments received from the public and interested stakeholders during the comment-response period. After the review and response to public comments, EPA formulates and publishes the final Regulatory Determination in a subsequent Federal Register notice. F or positive determinations (i.e., determinations to regulate a contaminant) this notice initiates the Regulation Development phase. Negativ e determinations (i.e., determinations not to regulate a contaminant) are considered a final agency action and this action is subject to judicial review. Negative determinations establish that contaminants are not occurring at levels and frequencies of public health concern in PWSs nationally

,, and thus provide confidence in the safety of the nation’s drinking water. When the agency decides not to regulate a contaminant, EPA may develop and issue a Health Advisory to guide state initiatives when a contaminant may be a local, but not a national concern. Contaminants that receive negative determinations are evaluated in future CCL development processe s to determine if new data are available on health effects and/or occurrence that warrant listing on future CCLs

. The following sections outline the technical protocol and analyses conducted by EPA to inform the RD 3 effort.



## 8. The Regulatory Determination 3 Process
As noted in section 2B, EPA is required to evaluate the following three statutory criteria when making regulatory determinations for CCL contaminants:EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

17 (1) The contaminant may have an adverse effect on the health of persons. (2) The contaminant is known to occur or there is substantial likelihood that the contaminant will occur in PWSs with a frequency and at levels of public health

concern

. (3) In the sole judgment of the Administrator, regulation of such contaminant presents a meaningful opportunity for health risk reduction for persons served by PWSs.

The agency is not able to make a regulatory determination for every contaminant on CCL 3 at this time. For some of the 116 CCL 3 contaminants, there is inadequate health and/or occurrence data to evaluate the contaminant against the three statutory criteria. As a result , EPA has developed a three

- phased protocol to identify contaminants that have sufficient information to apply the three statutory criteria , with a priority of identifying contaminants known to occur or with substantial likelihood to occur with a frequency and at levels of public health concern.

Th e three phases of the RD 3 Process are (1) the Data A vailability Phase, (2) the Data Evaluation Phase

, and (3) the Regulatory Determination Assessment Phase

. The overall RD 3 Process is displayed in Exhibit 6. The purpose of the first phase, the Data Availability Phase

, is to determine if EPA “may have” sufficient data to characterize the potential health effects and known or likely occurrence in drinking water. Although contaminants must have sufficient data to evaluate the statutory criteria in Phase 3, EPA does not want to rule out any contaminants too early in the process therefore, i f sufficient health and occurrence data “are likely” available, the contaminants are placed on a “short list” for the Data Evaluation Phase , the second phase of the
reg ulatory determination process.

During this second phase, EPA further evaluates each contaminant on the short list to identify those which have sufficient data (or were expected to have sufficient data by Fall 2011) for EPA to assess the three statutory cri teria. As part of the second phase, EPA specifically focuses its efforts to identify those contaminants or contaminant groups that are occurring or have substantial likelihood to occurat levels and frequencies of public health concern, based on the best a vailable data

. If EPA finds that sufficient data are not available or likely to be available to evaluate the three statutory criteria during the first and second phases, then the contaminant is not considered a candidate for making a regulatory determination and the contaminant is referred to the OGWDW Research Team to find potential avenues to fill data gaps 4

. If sufficient data are (or will be) available for a contaminant to characterize the potential health effects and known or likely occurrence in drinking water, the contaminant is evaluated against the three statutory criteria in the Regulatory Determination Assessment Phase , which is the third

4 OGWDW has a separate process for identifying and prioritizing research needs for the various drinking water projects. OGWDW coordinates with the Office of Research and Development (ORD) as well as other partners to fin d avenues to fill these data gaps (e.g., including a contaminant on the next round of UCMR, developing an analytical method, conducting a health assessment).EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

18 phase of the approach. The following sections discuss the steps involved in the three primary phases of the RD 3 Process.

The results of these three phases , information from the expert panel review, and other relevant information (such as population exposed and information on sensitive populations and lifestages) will be presented to the Administrator to determine whether regulation of the contaminant presents a meaningful opportunity for public health protection and to make preliminary decisions for RD 3. Th ese preliminary decisions will be published in the Federal Register for public comment. EPA will analyze and respond to the comments and issue the final Regulatory Determination 3 in the Federal Register

.
Exhibit 6 : The Three Primary Phases of the Technical Assessment of the Regulatory Determination 3 Process.

Health Data Availability Assessment

• Health Assessment available or in process Occurrence Data Availability Assessment

• Nationally representative finished water data “or”

• Other finished water data with detects greater than CCL3 derived HRL

Evaluation of Outcomes of Health & Occurrence Data Availability Assessments Does it potentially have sufficient health and occurrence data available? Phase 1: Data Availability

Phase 2: Data Evaluation Phase 3: Regulatory Determination Assessment

Step 1: Collect & Evaluate Health Information and Derive a Draft HRL

Step 2: Gather & Evaluate Additional

Occurrence Data Sources Relative to the Draft HRL Evaluate Statutory Criterion #2: Occurrence Assessment Is the contaminant known to occur or is

there substantial likelihood that the contaminant will occur above the HRL at a

frequency and level of public health concern? Evaluate Statutory Criterion #1: Health Assessment May the contaminant have an adverse effect on the health of persons?

Evaluate Statutory Criterion #3: Meaningful Opportunity Assessment (Administrator’s Decision) In the sole judgment of the Administrator,

does regulation of such contaminant present a meaningful opportunity for health risk reduction for persons served by public water systems? CCL 3

Step 3: Identify Contaminants Occurring at Levels and Frequencies of Public Health Concern

Step 4: Identify Contaminants with No or Low Occurrence at Levels of Public Health Concern



### 8.A. Phase 1: Data Availability Within the Data Availability Phase, two primary assessments are conducted in parallel: the Health Data Availability Assessment and the Occurrence Data Availability Assessment. Performing both assessments in parallel helps the agency identify those contaminants that may have sufficient health and occurrence data to be placed on the “short list” for further evaluation in the Data Evaluation Phase (Appendix D summarizes the data for Phase 1).EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

19 8.A.1. Health Data Availability Assessment In making a regulatory determination for a contaminant, SDWA requires that the a gen cy assess whether the contaminant “may have an adverse effect on the health of persons.” The agency relies on externally peer

- reviewed h ealth a ssessments to determine if, how, and at what level a contaminant “may have an adverse effect on the health of persons.”

As part of the CCL 3 process, health effects data sources were compiled for e ach of the 116 CCL 3 contaminants from one of the following EPA offices or other organizations: the agency's Integrated Risk Information System (IRIS), the a gency’s Office of Water (OW), the agency's Office of Pesticide Programs (OPP), the National Academy of Sciences (NAS), the Agency for Toxic Substances and Disease Registry (ATSDR), W orld Health Organization (WHO) [including Joint FAO/WHO Expert Committee on Food Additives (JECFA), Joint FAO/WHO Meeting on Pesticide Residues (JMPR)

, etc.]

, the California EPA’s Office of Environmental Health Hazard Assessment (OEHHA)

, Registry of Toxic Effects of Chemical Substances (RTECS) , and/or supplemental data from a single study (USEPA, 2009c). The health data compiled in CCL 3 is useful to establish that the contaminant has an adverse health effect but since CCL 3 is a screening level process the agency is less stringent on the type of health data sources used in CCL 3 compar ed to RD 3.

In the case of RD 3, the Health Data Availability Assessment is used to identify those among the 116 CCL 3 con taminants that have an externally peer

- reviewed health assessment either completed or in process from EPA and/or one of the designated non- EPA sources discussed below.

8.A.1.a. Is a Health Assessment Available or In Process? For contaminants in drinking water, an externally peer -reviewed health assessment prepared by EPA (i.e., either IRIS, OW, or OPP) generally addresses exp osure , toxicokinet ics, hazard identification, and dose-response for oral routes of exposure. For RD 3, certain non- EPA externally peer

- reviewed health assessment s (namely, from NAS, ATSDR, and WHO) were also considered for regulatory determinations if the health assessment used comparable methods, standards, and guidelines to an EPA health assessment. These non- EPA health assessments were recognized by the agency because of their standardized methods for characterizing health effects data, relevancy to drinking water exposures, and comparability to EPA methods . The designated health assessment data sources for RD 3 are explained further in Appendix B.

A primary health effects data source was selected for each CCL 3 contaminant. A literature search was condu cted to identify any CCL3 contaminant with a completed health assessment from a designated data source for RD 3 (IRIS, OW, OPP, NAS, ATSDR and WHO) since the publication of the Final CCL 3 Information Sheets in August 2009 (USEPA, 2009l). For those contaminants with no new health assessment, the health effects data source compiled during CCL 3 was used as the primary health effects data source for RD 3 . In general, an externally
peer

- reviewed EPA health assessmen t was preferred over a desig nated non- EPA health
assessment if both were available.

If a suitable health assessment is available or in process from a designated data source , the contaminant proceeds to the Evaluation of Outcomes of the Health and O ccurrence Data Availability Assess ment s (see section 8.A.2). For these contaminants, the potential health effects, the reference dose (RfD) or other non- cancer -health value, and/or cancer slope factor (CSF) fromEPA – OGW DW Protocol for Regulatory Determination 3 April 2014

20 each health assessment are compiled, as well as the date of the assessment . This information will b e used if the contaminant moves to Phase 2

. If a health assessment is not available or in process from one of the designated sources stated above, then the contaminant is not considered for this round of Regulatory Determination a nd the contaminant is referred to the OGWDW Research Team to find potential avenues to fill health effects data gaps and/or develop a health assessment.

8.A.2. Occurrence Data Availability Assessment The O ccurrence Data Availability A ssessment is used to identify contaminants that may have sufficient data and information to characterize known or likely occurrence in public water systems to address the second statutory criterion. EPA uses data from many sources to evaluate

occurrence for contaminants considered for regulatory determinations (see Appendix C). When making a regulatory determination for a contaminant, the agency prefers to have nationally representative finished drinking water occurrence data, but non

- national data may also be used for RD 3. The steps for this assessment involve answering the following two questions (discussed in sections 8.A.2.a and 8.A.2.b):

• Are nationally representative finished water occurrence data available?

• Are non- national finished water occurrence data available that show occurrence at levels of public health concern?

In addition, the a gency also identifies supplemental sources of information (e.g., ambient/source
water occurrence , production/ use, release, etc).

8.A.2.a. Are Nationally Representative Finished Water Occurrence Data Available? Nationally representative data are the primary source of the drinking water occurrence data used to evaluate whether or not a contaminant is “known to occur” in PWSs with a frequency and at levels of public health concern. If a contaminant has data available from at least one of the following data sources, which are administered or overseen by EPA , then it has nationally representative drinking water occurrence data:

• Second Unregulated Contaminant Monitoring Regulation (UCMR2)

.

• First Unregulated Contaminant Monitoring Regulation (UCMR1)

.

• Unregulated Contaminant Monitoring (UCM) program.

• National Inorganics and Radionuclides Survey (NIRS)

. These data sources are explained further in Appendix C. If nationally r epresentative occurrence data are available, a contaminant proceeds to the Evaluation of Outcomes of Health and Occurrence Data Availability Assessments step. If a contaminant does not have national data, EPA evaluates whether pertinent non -national data are available in the next step (8.A.2.b).

8.A.2.b. Are Non

- National Finished Water Occurrence Data Available that Show Occurrence at Levels of Public Health Concern? If nationally representative occurrence data are not available

, EPA identifies and evaluates nonnational finished water data for consideration in the regulatory determination process. These data include:EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

21 • Finished water a ssessments by federal agencies (e.g., EPA and the United States Geological Survey (USGS) ) . These may be assessments that are geographically distributed across the nation but not intended to be statistically representative of the nation.

• State

- level finished water monitoring data.

• Research performed by institutions and universities (e.g., scientific literature)

.

Non -national data may be “sufficient” to evaluate the statutory criteria and support regulatory determination in some cases. It is difficult to determine that a contaminant is not occurring or not likely to occur based on non- national data because the data are limited in scope and the contaminant could be occurring in other parts of the country that have not been monitored. However, a compilation of non- national data sources can support a determination that there is a “substantial likelihood that the contaminant will oc cur in PWSs with a frequency and at levels of public health concern.” Therefore, a contaminant with non- national occurrence data is evaluated further to determine whether the contaminant is occurring at a level of public health concern

. The purpose of this step is to not rule out any contaminants too early in the process that may have occurrence at levels of public health concern in finished water.

In this phase, the a gency assesses whether non -national finished water occurrence data show at least one det ection in finished water at levels > 1⁄2 CCL 3 HRL 5 for the critical endpoint (see Appendix A for a description of how an HRL is derived). If a contaminant has non-national finished water occurrence data showing at least one detection > 1⁄2 CCL 3 HRL, the contaminant proceed s to the Evaluation of Outcomes of Health and Occurrence Data Availability Assessment (section 8.A.3). If no national or non- national data are available, the contaminant is not considered for this round of Regulatory Determination an d the contaminant is referred to the OGWDW Research Team to find potential avenues to fill occurrence data gaps

.
8.A.3. Evaluation of Outcomes of Health and Occurrence Data Availability Assessments After conducting the Health and Occurrence Data Availabil ity Assessments, the agency identifies those contaminants that meet the following data availability crit eria :

• An externally peer- reviewed h ealth assessment from a designated source is available or in
process

.

• A widely available analytical method for monito ring 6 exists

.

5 For RD 3, the agency uses the CCL 3 HRL in this phase unless a completed peer

- reviewed health a ssessment from a designated data source has been identified since the CCL 3 information sheets were published in 2009 (USEPA, 2009l). Once the agency further evaluates the information in the most recent peer

- reviewed health assessments identified in this p hase, the agency may derive a draft HRL in phase 2, which may be different from the CCL 3 HRL. The CCL 3 HRLs for the 116 contaminants can be found at: http://water.epa.gov/scitech/drinkingwater/dws/ccl/upload/Final

- CCL -3- Contaminant

- Information

- Sheets.pdf . Note that HRLs are not final determinations about the level of a contaminant in drinking water that is necessary to protect any particular population (i.e., MCLG)

. 6 A widely available analytical method is a method employing technology that is commonly employed and in use at numerous drinking water laboratories. The CCL 3 microbes did not have a widely available analytical method forEPA – OGW DW Protocol for Regulatory Determination 3 April 2014

22 • E ither (a) national finished w ater occurrence data are available , or (b) non-national finished water occurrence data showing occurrence at levels > 1⁄2 CCL 3 HRL are available 7

.

• If a contaminant meets all of these criteria, it is placed on the “short list” and proceeds to Phase 2, the Data Evaluation Phase

. If any of these criteria are not met, no determination is made for these contaminants. In these cases, t he agency identifies the information gaps that p revent these contaminants from moving forward. The contaminants may be considered for the next CCL. In some cases, if a contaminant does not meet the criteria for moving forward, it may proceed to Phase 2 for further evaluation as a member of a
group of co ntaminants that meet s all criteria. Contaminant groups are defined by the factors discussed in the D WS (section 6).

8.A.4. Outcome of Phase 1 for Regulatory Determination 3 After evaluating the 116 CCL 3 contaminants in Phase 1, the agency identified 35 of them for placement on the “short list ” for continuation to Phase 2. Alongside the 35 short- listed CCL 3 contaminants, EPA also identified two non-CCL 3 nitrosamines, n-nitroso-di-n-butylamine (NDBA) and n -nitrosomethylethylamine (NMEA) for inclusion in Phase 2 . Although the se two contaminants were not listed on CCL 3, they met the criteria described above for inclusion on the short list and the agency thought it advisable to evaluate them alongside other nitrosamines. The contaminants selected for evalua tion in Phase 2 are listed in Exhibit 7.

Exhibit 7 : Contaminants to be Evaluated in Phase 2 of the Regulatory Determination Process 1,1,1,2

- Tetrachloroethane 1,3 Metolachlor oxanilic acid (OA) 1,3

1,2,3

- Trichloropropane 1,3 Molinate 1

1,3

- Dinitrobenzene 1 Molybdenum 1

1,4

- Dioxane 2 Nitrobenzene 1,3

Acephate 2 N

- N itroso

- di

- n

- butylamine (NDBA) 1 ,3,5

Acetochlor 1,3 N

- Nitrosodiethylamine (NDEA) 1,3

Acetochlor ethanesulfonic acid (ESA) 1,3 N

- N itrosodimethylamine (NDMA) 1,3

Acetochlor oxanilic acid (OA) 1,3 N

- Nitroso

- di

- n

- propylamine (NDPA) 1,3

monitoring and were not placed on the “short list” for Regulatory Determination 3 for this reason.
7 One exception to this criterion applies to contaminants monitored in the UCMR 1 Screening Survey (SS). As noted in section 5, the UCMR 1 SS is a statistically defined, national sample of PW Ss. Because this survey only includes 300 systems, the agency identified and compiled additional supplemental data to compliment the UCMR 1 SS data for contaminants that proceed to the Phase 2 evaluation for further evaluation on this basis.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

23 Alachlor ethanesulfonic acid (ESA) 1,3 N

- Nitrosodiphenylamine (NDPhA) 3

Alachlor oxanilic acid (OA) 1,3 N

- N itrosomethylethylamine (NMEA) 1 ,3,5

Chlorate 2 N

- N itrosopyrrolidine (NPYR) 1,3

Cobalt 1 Perfluorooctane sulfonic acid (PFOS) 2

Dimethoate 1 Perfluorooctanoic acid (PFOA) 2

Disulfoton 4 RDX 1

Diuron 4 Strontium 1

Methyl bromide (Bromomethane) 1 Terbufos 2,3

Methyl tert

- butyl ether 1 Terbufos sulfone 1,3

Metolachlor 1,3 Vanadium 1

Metolachlor ethanesulfonic acid (ESA) 1,3

1 Has national ly representative finished water data and available or in process health
assessment

2 Has other finished water data (occurrence at levels > 1⁄2 CCL 3 HRL) and an available or in

- process health assessment

3 Compon e nt of a contaminant group and will be further evaluated in Phase 2

4 One exception to the criterion of having available national ly representative drinking water data applies to contaminants monitored in the UCMR 1 Screening Survey (SS). As noted in section 5, the UCMR 1 SS is a statistically defined, national sample of 300 PWSs. Because this survey only includes 300 systems, the agency identified and compiled additional supplemental data to compliment the UCMR 1 SS data for these contaminants that proceed to Phase 2 for further evaluation.

5 A non

- CCL 3 contaminant that is part of the nitrosamine group.

The remaining 81 CCL 3 contaminants did not advance and were not considered in RD 3 because the agency lack ed the following data/information sources that are necessary to evaluate the three SDWA criteria: (a) an IRIS, OPP, OW, NAS

, ATSDR or WHO health assessment that can be used to fully characterize the critical health effect and derive a draft HRL and/or (b) national occurrence data to characterize occurrence in public water systems or non -national data showing at least one detection greater than 1⁄2 the CCL 3 HRL . Appendix D provides the full set of information us ed to arrive at this outcome

.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

24 

### 8.B. Phase 2: Data Evaluation The Regulatory Determination “s hort l ist ” is a list of contaminants that have been identified in Phase 1 as having sufficient data to warrant expanded assessment. SDWA requires the agency to make determinations for at least five (5) of the contaminants on the CCL and to select for regulatory determination “contaminants that present the greatest public health concern,” including consideration of sensitive subpopulations ( SDWA § 1412(b)(1)(B), (C)). The purpose of Phase 2 is to:

(1) E valuate the health and occurrence data for the “short lis t” contaminants more thoroughly. (2) Identify contaminants occurring with levels and frequencies of public health concern. (3) Identify contaminants that have no or low potential for public health concern. (4) Identify contaminants that have potential information or data gaps that may prevent them from moving to the next phase (Phase 3).

The steps involved in the Data Evaluation Phase are described in the sections that follow. Note that the agency does not have a threshold for health or occurrence values that trigger whether or not a contaminant is of public health concern. There are a number of factors to consider in evaluating potent ial public health concern , some of which include the health effect(s), the potency of the contaminant, the concentrations at which the contaminant is occurring, how frequently the contaminant is found, the geographic distribution (national, regional, or lo cal occurrence), other possible sources of exposure, potential impacts on sensitive populations or lifestages, etc. Given the many possible combinations of factors and the constantly evolving science, EPA believes it is best to analyze each contaminant and present the best available information that helps identify whether or not the occurrence of a contaminant is of public health

concern (Appendix E summarizes the key data for Phase 2 evaluations)

.
8.B.1. Phase 2

-- Step1: Collect and Evaluate Health Informa tion and Derive a Draft HRL In Phase 1, the a gency identified available health assessments or health assessments that are in
process from the designated sources

. Using the health effects assessments compiled in Phase 1 (listed in Appendix D) , a draft HRL is derived. In some cases, the health assessment or the HRL derived from the health assessment may need updating based on the following reasons:

• P eer -reviewed publications have been identified through the literature after health assessment publication 8

.

• The health assessment was published prior to 1996 and does not follow current agency guidelines and standards. 9

8 The OW perfo rms a literature search for studies published after the available health assessment (i.e., Phase 1) is completed to determine if new information suggests a different outcome. The agency collects and evaluates any
peer

- reviewed publications identified through the literature search for their impact on the RfD and/or cancer assessment. In cases where the recent data indicates that a change to the existing RfD or cancer assessment is needed, an OW assessment may be prepared and independently peer

- reviewed.
9 Contaminants that have quantitative cancer assessments conducted under the 1986 Guidelines for Carcinogen Risk Assessment (USEPA, 1986) would need to be updated using the more recent 2005 Guidelines for Carcinogen Risk Assessment (USEPA, 2005b), the Supple mental Guidance for Assessing Susceptibility from Early

- life Exposures toEPA – OGW DW Protocol for Regulatory Determination 3 April 2014

25 • The health assessment is from a non -EPA source (e.g., NAS, ATSDR and WHO ) and may need to be updated to follow current agency guidelines and stan dards (see Appendix B)

.
In other cases, the CCL 3 HRL is used as the draft HRL if the health assessment is from a designated source and does not need to be updated.

EPA made Fall 2011 the cutoff point for completed health assessments for preliminary de terminations for RD 3. If it was judged that an assessment could not be updated or completed by Fall 2011, the contaminant d id not proceed to Phase 3.

8.B.1.a. Derivation of the Draft HRL and Consideration of Sensitive Populations HRLs are not final determinations about the level of a contaminant in drinking water that must not be exceeded to protect any particular population; they are derived prior to development of a complete exposure assessment

. HRLs are risk

- derived concentratio ns against which to evaluate the occurrence data to determine if contaminants occur at levels of potential public health

concern. All adverse health effects (e.g., cancer, thyroid effects, reduced body weight etc.) are considered to be of equal importance when evaluating the occurrence above the draft HRL. The differences in health risk between the adverse health effects for each contaminant are reflected in the RfD or CSF and the HRL derivation methods. There are two general approaches to the derivation o f an HRL. One approach is used for chemicals that cause cancer and exhibit a linear response to dose and the other applies to non-carcinogens and carcinogens evaluated using a non-linear approach. The derivation of HRLs for carcinogens and non-carcinogens are described in Appendix A.

In evaluating contaminants for regulatory determination, Section 1412 (b)(1)(A)(i) of SDWA requires the agency to consider “among other factors of public health concern , the effect of such contaminants upon subgroups that comprise a meaningful portion of the general population (such as infants, children, pregnant women, the elderly, individuals with a history of serious illness, or other subpopulations) that are identifi able as being at greater risk of adverse health effects due to exposure to contaminants in drinking water compared to the general population.” If appropriate and if available, the a gency quantitatively takes into account data from sensitive populations an d lifestages when deriving HRLs for regulatory determinations in the following manner:

(a.) For non- carcinogens, an HRL can be developed for a sensitive population if high quality data are available to associate exposure with the critical health endpoint in a specific group or during a specific period of sensitivity. Age-specific drinking water intake body weight ratio values from the Exposure Factors Handbook (USEPA, 2011d) can be used to reflect the period of exposure more accurately. The agency can also apply specific uncertainty factors (UFs) when deriving the RfD if toxicological data are lacking for a sensitive population. UFs are usually applied as integers of one, three, or ten. Two common UFs that can be applied to account for sensitive populations are : (1) variation in sensitivity among the members of the

Carcinogens (USEPA, 2005c), and the Exposure Factors Handbook (USEPA, 2011 d ). These guidelines include new considerations for contaminants with a mutagenic mode of action and potential risks due to early childhood exposure (USEPA 2005b; 2005c).EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

26 human population (i.e., intraspecies variability) and (2) uncertainty associated with an incomplete databa se (Appendix A ).

(b.) For HRLs developed for carcinogens with a mutagenic mode of action (MOA), the 2005 Cancer Guidelines require consideration related to increased risks due to early -life exposure. When chemical

- specific data to quantify the increased risk are lacking, Age Depe ndent Adjustment Factors (ADAFs) are applied, with a 10 -fold adjus tment for early life exposures, a 3 -fold adjustment for childhood/adolescent exposures, and no additional adjustment for exposures later in life. Age -specific drinking water intake body weight ratio values are also applied from the Exposure Factors Handboo k ( USEPA, 2011 d) . In cases where the data on the MOA are lacking, a default low -dose linear extrapolation approach without ADAFs is used (Appendix A ).

In addition to quantitatively address ing sensitive populations when deriving the HRL , the agency also performs a literature review of scientific data covering developmental and reproductive endpoints (e.g., fertility, embryo survival, developmental delays, birth defects, and endocrine effects) which is compiled and evaluated qualitatively. The sensitive populations identified for short list contaminants are listed in Appendix E and Appendix F.

When t he draft HRL has been established, it is used in the following steps to evaluate the occurrence information and identify contaminants of public health concern.

8.B.2. Phase 2

-- Step 2: Gather and Evaluate A dditional O ccurrence Data S ources R elative to the Draft HRL In this step, the a gency compiles, analyzes , and evaluates the national or non- national occurrence information identified in Phase 1 against the dra ft HRL (developed as described in section 8.B.1) as well as the minimum reporting level (MRL)

. The a gency also compiles additional occurrence data and information on monitoring in ambient or source water (relative to the draft HRL and also the detections a t the minimum reporting limit), production, use, release to the environment, and persistence and mobility. This information will be used in steps 3 and 4 of Phase 2 (see 8.B.3 and 8.B.4), and also in Phase 3 if a contaminant proceeds to that phase.

8.B.3. Phase 2

-- Step 3: Identify C ontaminants Occurring at Levels and Frequencies of Public Health Concern In this step, the a gency identifies contaminants occurring at levels and frequencies of public health concern that will proceed to Phase 3, the Regulatory Determination Assessment Phase

. The candidate contaminants identified in this step are the highest priority for R D 3 and for the completion of their health assessments, if necessary. The agency considers the following information when identifying these con taminants:

• How many samples (# and %) have detections > draft HRL and 1⁄2 draft HRL in the national and non- national finished water occurrence data?

• How many systems (# and %) have detections > draft HRL and 1⁄2 draft HRL in the national and non-national finished water occurrence data?EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

27 • Is the contaminant associated with a contaminant group t hat is of public health concern and is being considered as part of the DWS (see factors considered for grouping under the DWS - section 6)? 10

• Are there uncertainties or limitations with the data and/or analyses, such as the age of the dataset, limitation of the detection limit (i.e., MRL > draft HRL) and/or representativeness of the data (e.g., limited scope to a specific region) that may cause underestimation of occurrence in finished water at levels and frequency of public health concern?

8.B.4. Phase 2

-- Step 4: Identify Contaminants That Have No or Low Occurrence at Levels of Public Health Concern After identifying contaminants in s tep 3 (8.B.3) that are o ccurring at levels and frequencies of public health concern , the agency evaluates the remaining contaminants on the short list to identify contaminants with no to low occurrence at levels of health concern that should proceed to Phase 3 for a potential negative determination

. Because t he primary goal of RD 3 is to focus on contaminants of public health concern and since the agency will likely make a decision “not to regulate” contaminants that have no to low occurrence at levels of public health concern, these contaminants are a lower priority for this effort. The a gency considers the following information in selecting contaminants of no or low potential for public health concern to proceed to Phase 3:

• Does the contaminant have national finished water data showing no or low # or % of detections > draft HRL 11 ?

• If a contaminant has other finished water data in addition to nationally representative finished water data , does it support no or low potential for occurrence in drinking water?

• Does additional occurrence information of known quality support low or no occurrence or potential for occurrence in drinking water? For example, is the occurrence in ambient/source water at levels below the draft HRL? Are releases to the environment or use/production decreasing over time?

• There are no critical information/data gaps after evaluating the available health or occurrence data

.

• The contaminant is not included or evaluated with a group of contaminants based on the factors defined by the DWS (e.g., cVOCs - see section 6).

If a contaminant meets all or most of these factors and appears to have sufficient data to evaluate the statutory criteria for regulatory determination, the contaminant moves onto Phase 3. These contaminants have sufficient data fo r EPA to make a determination that they do not occur at levels and frequencies of public health concern in drinking water, including national finished water data . If any of these contaminants receive negative determinations as part of RD 3, they will be co nsidered for the next round of the CCL if new data becomes available.

10 Carcinogenic Volatile Organic Compounds (including 1,2,3

- trichloropropane) are being evaluated in a separate regulatory effort.
11 Note that non

- national data tend to be limited in scope and EPA does not use them to support a determination that the contaminant is not or is not substantially likely to “occur in PWSs with a frequency and at levels of public health concern” and therefore a decision “not to regulate” (i.e.

, negative determination)

.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

28 The remaining contaminants do not proceed to Phase 3 and are therefore not considered for this round of regulatory determination (i.e. , “no determination” is made ). They will be consider ed for the next CCL. The agency identifies the health

, occurrence , and/or other data gaps that prevent these contaminants from moving forward and evaluate s potential avenues to fill those gaps (e.g.

, inclu sion in the next round of UCMR, develop ing an analytical method, conducting a health assessment)

.
8.B.5. Outcome of Phase 2 for Regulatory Determination 3 After evaluating the 35 “short list” CCL 3 contaminants identified in 8.A.4 according to the steps in Phase 2, the agency determined that 10 CCL 3 contaminants ( plus two non CCL 3 contaminants, NDBA and NMEA ) 12 should proceed to Phase 3, the Regulatory Determination Assessment Phase

. The 1 0 CCL 3 contaminants, divided into two bins, are :
“Occurring or Likely to Occur at Levels and Frequencies of Public Health Concern”

• Chlorate

.

• N-Nitrosodimethylamine (NDMA)

.

• N-N itroso

- di -n-propylamine (NDPA).

• N-Nitrosodiethylamine (NDEA).

• N-N itrosopyrrolidine (NPYR)

.

• Strontium

.

“ No t Occurring or Likely to Occur at Levels and Frequencies of Public Health Conc ern ”:

• Dimethoate.

• 1,3-Dinitrobenzene.

• Terbufos.

• Terbufos sulfone.

As part of the DWS , 1,2,3-trichloropropane, 1,1,1,2-tetrachloroethane and n itrobenzene 13 are being evaluated and considered for the Carcinogenic Volatile Organic Compounds (CVOCs) group rule under development . Because they are being addressed in a separate process, they were excluded from Phase 3 under RD 3.The remaining 22 contaminants d id not proceed to Phase 3 because of one or more of the following critical health, occurrence and/or other data gaps:Health:

• An updated health assessment is needed but was not completed by Fall 2011.

• A health assessment wa s in process and was not completed by Fall 2011.

12 NDBA and NMEA are being considered alongside four CCL 3 nitrosamines (NDEA, NDMA, NDPA, and NPYR) as part of the group approach under DWS. These compounds meet several factors for potential grouping, including similar health endpoints, a common analytical method, susceptibility to the same treatment technologies or approaches, and documented co

- occurrence. A seventh nitrosamine, NDPhA , had no EPA analytical method suitable for monitoring so it did not move forward to Phase 3 and is not being evaluated a longside the others under the group approach.
13 Some of these contaminants were referred to the CVOC group after EPA’s February 2011 announcement about the CVOC group (see http://water.epa.gov/lawsregs/rulesregs/sdwa/dwstrategy/index.cfm ).EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

29 • Critical health effects gap ( e.g., lack of data to support quantification for the oral route of exposure).

Occurrence:

• Lacks national occurrence data

.

• Insufficient non- national occurrence data to demonstrate occurrence at levels and frequencies of public health concern (although it may have some levels of public health concern)

.

• Individual contaminant that is part of a group but l ack s a widely available analytical method for occurrence monitoring

.

• Critical occurrence data gap (e.g., inconsistent results and/or trends in occurrence data, significant uncertainty in occurrence analyses and/or d ata)

.


### 8.C. Phase 3: Regulatory Determination Assessment

• The Regulatory Determination Assessment Phase involves a complete evaluation of the statutory criteria for each contaminant or group of contaminants that have passed Phase 2 and have sufficient information and data for making a regulatory determination. In this phase, the a gency evaluates the following statutory criteria: Statutory Criterion #1: Might the contaminant have an adverse effect on the healt h of persons?

• Statutory Criterion #2: Is the contaminant known to occur or is there a substantial likelihood that the contaminant will occur in PWSs with a frequency and at levels of public health concern?

• Statutory Criterion #3: In the sole judgment of the Administrator, does regulation of such contaminant present a meaningful opportunity for health risk reduction for persons served by PWSs?

The following steps discuss the factors that the a gency considers in evaluating each of these statutory criteria. Note that the third statutory criterion is the Administrator’s decision.

8.C.1. Evaluation of Statutory Criterion #1 (Adverse Health Effect) The contaminants for RD 3 are generally expected to meet statutory criterion #1 because their adverse health effects were analyzed as part of the determination to list them on the CCL 3

. During the CCL 3 process, the critical health effect was identified and the level of potency (a value that indicates the lowest dose of a chemical that causes the adverse health effe ct) and severity (the relative impact of the adverse health effect) of the health effect was evaluated ( USEPA, 2009 g ); therefore the answer to the health statutory criterion that the contaminant “may have an adverse effect on the health of persons” is typically “yes.” More importantly, the evaluation of the first statutory criterion includes the completion of any health assessment that needed to be updated and externally pee r-reviewed, and the derivation of the final peer- reviewed HRL ( Appendix A ) to define the dose at which adverse health effects are likely to occur. The derivation of the final HRL takes into account many of the key elements that are considered when evaluati ng the first criterion, which include the mode of action, the critical health effect(s), the dose- response for critical health effect(s), impacts on sensitive population(s) or lifestages, the RfD, and/or the CSF . As noted earlier, the HRL is not a final determination about the level of a contaminant in drinking water that must not be exceeded to protect any particular population (i.e., a maximum contaminant level goal) . The HRL is derived prior to development of a complete exposure assessment

. The HRL is a risk -derived concentration against which EPAEPA – OGW DW Protocol for Regulatory Determination 3 April 2014

30 compares the concentrations of a contaminant found in public water systems to determine if the levels are of potential public health concern.

8.C.2. Evaluation of Statutory Criterion #2 (Known or Likely Occurrence in PWSs with a Frequency and Level of Concern) The occurrence data for each contaminant are compared to the final peer -reviewed HRL to determine if the contaminant occurs at a frequency and levels of public health concern. The following factors, further refined from the previous phase and categorized by importance (i.e., primary versus additional), are considered when identifying contaminants or contaminant groups that are of public health concern:

8.C.2.a. Factors of Primary Consideration

• How many samples (# and %) have detections > final HRL in the national and nonnational finished water occurrence data?

• How many systems (# and %) have detections > final HRL in the national and nonnational finished water occurrence data?

• Is the contaminant a ssociated with a contaminant group that is of public health concern and is being considered as part of the DWS (see factors considered for grouping under the DWS - section 6 )?

• Is the geographic distribution of contaminant occurrence national, regional, or localized?

• In addition to the number of systems, what type of systems does the contaminant occur in? Does the contaminant occur in large or small systems? Does the contaminant occur in surface or ground water systems?

• Are there significant uncertainties or limitations with the data and/or analyses, such as the age of the dataset, limitation of the analytical method (e. g., MRL > final HRL) , or representativeness of the data ( e.g., limited in scope to a specific region)?

8.C.2.b. Addition al Factors of Consideration

• How many samples (# and %) have detections > 1⁄2 final HRL 14 in the national and nonnational finished water occurrence data?

• How many systems (# and %) have detections > 1⁄2 final HRL in the national and nonnational finished water occurrence data?

• How many samples (# and %) have detections > final HRL and 1⁄2 final HRL in the ambient/source water occurrence data?

• How many sites (# and %) have detections > final HRL and 1⁄2 final HRL in the ambient/source water occurrence data?

• Are production and use trends for the contaminant increasing or decreasing?

• How many pounds are discharged annually to surface water and/or released to the environment?

• Do the environmental fate and transport parameters indicate that the contaminant would persist and/or be mobile in water?

14 Occurrence is also evaluated relative to 1⁄2 of the HRL as a more conservative estimate of the occurrence at or approaching levels of public health concern.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

31 • Is the contaminant introduced by water treatment processes (e.g. , disinfection byproducts)?

• Are there uncertainties or limitations with the data and/or analyses for these additional factors that should be considered?

If a contaminant is known to occur or substantially likely to occur at a frequency and level of health concern in public water systems based on the factors listed above, then the agency answers “yes” to the second statutory criterion. Otherwise, the agency answers “no” to the second statutory criterion.

An important consideration in this evaluation is the detection limit (DL) and/or the reporting level (RL) , sometimes designated as a minimum reporting level (MRL) , used in monitoring for drinking water cont aminants. The DL is the minimum concentration of a contaminant in water that can be reliably differentiated from the signal arising from a blank (i.e., the contaminant can be determined to be present), al though it typically is not possible to achieve relia ble quantitation at the DL . The RL is a concentration at or above which results are reported by a laboratory or a study author, and is generally a concentration at which reliable quantitation is possible. The MRL is the minimum concentration that is requir ed to be reported in a study. The MRL is usually set at a value that takes into account typical laboratory capabilities to detect and quantify a compound and the cost of increasingly precise measurements. If the HRL is equal to or greater than the MRL , any occurrence above the HRL can be reliably quantified and reported with confidence. If the HRL is less than the MRL , any reported concentration (commonly called a “detection”) is greater than the HRL. Occurrence at concentrations that exceed the HRL bu t are below the MRL will go unreported. A variety of approaches can be used to estimate the

occurrence below the MRL, including fitting an appropriate distribution model

. In the case of carcinogens, i f there is little to no occurrence at an MRL that is gr eater than an HRL and the MRL is within the 10 -4 to 10 -6 risk range, the a gency can mak e a decision for the second statutory criterion as long as this limitation is noted and other information/data are considered (e.g., contaminant manufacturing trends, tr ends in the amount released to the environment, occurrence in ambient water, etc.).

8.C.3. Evaluation of Statutory Criterion #3 (Meaningful Opportunity) In the end, it is up to the sole judgment of the Administrator to decide whether a drinking water regulation for a contaminant presents a meaningful opportunity for health risk reduction for persons served by public water systems. An explanation of the factors the Administrator considers is presented in Appendix G.

8.C.4. Making a Regulatory Determina tion Decision As noted earlier, the agency does not make a determination for those contaminants that do not have sufficient information to answer the three SDWA statutory criteria (Exhibit 8 ).

If a contaminant has sufficient information and the agency answers “yes” to all three statutory criteria for a particular contaminant (Exhibit 8), then the a gency makes a “positive”EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

32 determination that regulation is necessary . When the positive determination is finalized, the agency has 24 months to publish a proposed MCLG and NPDWR and 18 months to publish a final MCLG and promulgate a final NPDWR (SDWA section 1412(b)(1)(E)) 15

. As noted previously, this regulatory determination process is distinct from the more detailed analyses needed to develop an NPDWR . Thus, a decision to regulate is the beginning of the agency's regulatory development process, not the end.

If a contaminant has sufficient information and the agency answers “no” to any of the three statutory criteria

, based on the available data, then the agency considers mak ing a “negative” determination that a n NPDWR is not necessary for that contaminant at that time. The agency may decide to develop a H ealth Advisory (HA), which provides non- regulatory concentration values for drinking water contaminants at which adverse health effects are not anticipated to occur over specific exposure durations (one-day, ten- days, several years, and a lifetime). HAs serve as informa l technical guidance to assist federal, state, and local officials, and managers of public or community water systems (CWSs) in protecting public health when emergency spills or contamination situations occur.

While a negative determination is considered a final agency action for this round of regulatory determination, the contaminant is considered in the next round of the CCL process and could be

re

- listed based on newly available health and/ or occurrence information

.

15 SDWA allows the agency to extend the promulgation date by 9 months.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

33 Exhibit 8 : Regulatory Determination Outcomes

8.C.5. Outcome of the Regulatory Determination Assessment Phase for Regulatory Determination 3 The summary sheets in Appendix F present the key data evaluated and the outcomes for statutory criteria 1 and 2

.



## 9. References Cited
Government Accountability Office (GAO). 2011. Safe Drinking Water Act: EPA Should Improve Implementation of Requirements on Whether to Regulate Additional Contaminants. Report to Congressional Requesters. GAO -11-254. May 2011. Available on the Internet at: http://www.gao.gov/products/GAO-11-254

. National Academy of Sciences ( NAS ). 2001. Classifying Drinking Water Contaminants for Regulatory Considerations

. Committee on Drinking Water Contaminants, Water Science and Technology Board, Board on Environmental Studies and Toxic ology, National Research Council

. National Drinking Water Advisory Council (NDWAC). 2004. National Drinking Water Advisory Council Report on the CCL Classification Process to the U.S. Environmental Protection Agency. May 19, 2004. Available on the Interne t at: http://www.epa.gov/safewater/ndwac/pdfs/report_ccl_ndwac_07-06-04.pdf

.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

34 United States Environmental Protection Agency ( USEPA ). 1986. Guidelines for Carcinogen Risk Assessment. Federal Register . Vol. 51, No. 185. p. 33992, September 24, 1986.

USEPA. 1997. Announcement of the Draft Drinking Water Contaminant Candidate List; Notice. Federal Register . Vol. 62, No. 193, p. 52194, October 6, 1997. Available on the Internet
at: https://federalregister.gov/a/97 -26433

USEPA. 1998. Announcement of the Drinking Water Contaminant Candidate List; Notice

. Federal Register . Vol. 63, No. 40, p. 10273. March 2, 1998. Available on the Internet at: https://federalregister.gov/a/98 -5313

USEPA. 1999a. Revisions to the Unregulated Contaminant Monitoring Regulation for Public Water Systems; Final Rule. F ederal Register . Vol. 64, No. 180, p. 50556. September 17, 1999. Available on the Internet at: https://federalregister.gov/a/99-23030

USEPA. 1999b. National Representative Sample of Small Water Systems: Statistical Design and State Plans for Unregulated Contaminant Monitoring. EPA 815-R-99-003.

USEPA. 1999c . National Representative Sample of Small Public Water Systems: Statistical Design and S tate Plans for the Unregulated Contaminant Monitoring Regulation. Offi ce of Water. EPA 815-R-99-003. August. 44 pp.

USEPA. 2001. Statistical Design and Sample Selection for the Unregulated Contaminant Monitoring Regulation. EPA 815 -R-01-004.

USEPA. 2002. Announcement of Preliminary Regulatory Determinations for Priority Contaminants on the Drinking Water Contaminant Candidate List. Federal Register . Vol. 67, No. 106, p. 38222, June 3, 2002. Available on the Internet at: https://federalregister.gov/a/02 -13796

USEPA. 2003. Announcement of Regulatory Determinations for Priority Contaminants on the Drinking Water Contaminant Candidate List. Federal Register . Vol. 68, No. 138, p. 42898. July 18, 2003

. Available on the Internet at: https://federalregister.gov/a/03 -18151

USEPA. 2004. Drinking Water Contaminant Candidate List 2; Notice. Federal Register . Vol. 69, No. 64, p. 17406, April 2, 2004. Available on the Internet at: https://federalregister.gov/a/04 -7416

USEPA. 2005a. Drinking Water Contaminant Candidate List 2; Final Notice. Federal Register

. Vol. 70, No. 36, p. 9071. February 24, 2005. Available on the Internet at: https://federalregister.gov/a/05 -3527

USEPA. 2005b. Guidelines for Carcinogen Risk Assessment. EPA 630 -P-03-001B. March 2005. Available on the Internet at: http://www.epa.gov/ttn/atw/cancer_guidelines_final_3-25- 05.pdf

.

USEPA. 2005c. Supplemental Guidance for Assessing Susceptibility to Early- life Exposure to Carcinogens. EPA 630 -R-03-003F. Ma rch 2005. Available on the Internet at: http://www.epa.gov/ttn/atw/childrens_supplement_final.pdf

.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

35 USEPA. 2007 a. Drinking Water: Regulatory Determinations Regarding Contaminants on the Second Drinking Water Contaminant Candidate List— Preliminary Determinations. Federal Register . Vol. 72, No. 83, p. 24016, May 1, 2007. Available on the Internet at: https://federalregister.gov/a/E7 -7539

USEPA. 2007b. Unregulated Contaminant Monitoring Regulation (UCMR) for Public Water Systems Revisions ; Final Rule

. Federal Register . Vol. 72, No. 2, p. 367. January 4, 2007. Available on the Internet at: https://federalregister.gov/a/E6 -22123

USEPA. 2008 a. Drinking Water: Regulatory Determinations Regarding Contaminants on the Second Drinking Water Contaminant Candidate List. Federal Register . Vol. 73, No. 147, p. 44251. July 30, 2008. Available on the Internet at: https://federalregister.gov/a/E8

- 17463

USEPA. 2008b. Drinking Water: Preliminary Regulatory Determination on Perchlorate. Federal Register

. Vol. 73, No. 198, p. 60262, October 10, 2008

. Available on the Internet at: https://federalregister.gov/a/E8 -24042

USEPA. 2008 c . Drinking Water Contaminant Candidate List 3

— Draft Notice. Federal Register

. Vol . 73. No 35. p. 9628, February 21, 2008. Available on the Internet at: https://federalregister.gov/a/E8 -3114

USEPA. 2008 d. The Analysis of Occurrence Data from the First Unregulated Contaminant Monitoring Regulation (UCMR 1) in Support of Regulatory Determinations for the Second Drinking Wa ter Contaminant Candidate List

. EPA 815 -R-08-012. June 2008.

USEPA. 2009 a. Drinking Water: Perchlorate Supplemental Request for Comments. Federal Register . Vo l. 74, No. 159, p. 41883, August 19, 2009. Available on the Internet at: https://federalregister.gov/a/E9 -19507

USEPA. 2009b. Drinking Water: Perchlorate Supplemental Request for Comments. Federal Regi ster. Vol. 74, No. 183, p. 45841, September 23, 2009. Available on the Internet at: https://federalregister.gov/a/E9 -22927

USEPA. 2009c. Final Contaminant Candidate List 3 Chemicals: Identifying the U niverse . EPA 815-R-09-006. August.

USEPA. 2009 d. Final Contaminant Candidate List 3 Microbes: Identifying the Universe, EPA 815–R–09–004. August.

USEPA. 2009 e. Final Contaminant Candidate List 3 Chemicals: Screening to a PCCL. EPA 815- R-09-007. August.

USE PA. 2009f. Final Contaminant Candidate List 3 Microbes: Screening to the PCCL, EPA 815–R–09–005. Draft. August.

USEPA. 2009 g . Final Contaminant Candidate List 3 Chemicals: Classification of PCCL to the CCL. EPA 815 -R-09-008. August.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

36 USEPA. 2009 h. Final Con taminant Candidate List 3 Microbes: PCCL to CCL Process, EPA 815–R–09–009. August.

USEPA. 2009i. Summary of Nominations for the Third Contaminant Candidate List. EPA -815- R-09-011. August.

USEPA. 2009j. Final Comment Response Document for the Third Drinking Water Contaminant Candidate List 3 Categorized Public Comments. EPA 815-R-09-010. August.

USEPA. 2009 k . Drinking Water Contaminant Candidate List 3 – Final. Federal Register . Vol. 74, No. 194, p. 51850. October 8, 2009. Available on the Internet at: https://federalregister.gov/a/E9 -24287

USEPA. 2009l. Final CCL 3 Contaminant Information Sheets. EPA 815-R-09- 012. August,.

U SEPA. 2011 a. Drinking Water: Regulatory Determination on Perchlorate. Federal Register

. Vol. 76, No. 29, p. 7762, February 11, 2011. Available on the Internet at: https://federalregister.gov/a/2011 -2603

USEPA. 2011 b. Summary of Comments and Discussion, Preliminary Regulatory De terminations for the Third Contaminant Candidate List Stakeholder Meeting, June 16, 2011.

USEPA . 2011c. Support for Regulatory Determination 3 Expert Reviews; October 26th and 27th 2011. Meeting Summary . December 2011.

USEPA. 2011 d. Exposure Factors Handbook 2011 Edition (Final). U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-09/052F.

USEPA . 2013. Response to External Expert Review of the Regulatory Determination 3 Protocol: Expert Review Comments with EPA Responses

.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

37 

## Appendix A. Health Reference Levels
A Health Reference Level or H R L is a health benchmark that the agency uses in the Regulatory Determination process to assess occurrence information. HRLs are not final determinations about the level of a contaminant in drinking wate r that is necessary to protect any particular population (i.e., MCLG). Rather

, it is a benchmark against which EPA compares the concentrations of a contaminant found in public water systems to determine if it is present at levels of public health

concern.
The 1996 SDWA Amendments require special consideration of all sensitive populations and lifestages (e.g., infants, children, pregnant women, elderly, and individuals with a history of chronic illness) in the development of drinking water regulations. If appropriate and available, the a gency takes into account data from sensitive populations and life stages when developing HRLs. The derivation of HRLs for carcinogens and non-carcinogens are shown below. Derivation of an HRL for Carcinogens

For those contaminants considered to be likely or probable human carcinogens, a toxicity value that defines the quantitative relationship between dose and response ( i.e., the cancer slope factor

or CSF)

, is calculated and data on the mode of action (MOA) are evaluated

.
Unidentified Mode of Action In cases where the data on the mode of action are lacking, EPA typically uses a default low dose linear extrapolation to calculate a CSF . The unit risk is the estimated upperbound excess lifetime cancer risk from a continuous exposure to a chemical at a concentration of 0.001 mg/L (1 μg/L) in drinking water. The exposure estimate assumes an adult body weight of 70 kg and a 90 th percentile adult drinking water intake of 2 L/day. Unit Risk (μg/L) -1 = CSF x [( DWI x CW)/BW]

where:

CSF = The Cancer Slope Factor (mg/kg/day) -1
DWI = Drinking W ater Intake for an adult, assumed to be 2 L/day (90 th percentile) CW = Unit risk concentration in drinking water of 0.001 mg/L (1 μg/L) ; BW = Body weight of an adult

, assumed to be 70 kilograms (kg)

The cancer HRL , which corresponds to an excess estimated lifetime cancer risk of one in a million (10 -6 ), is calculated by div iding the population risk level by the unit risk:

HRL (μg/L) = Risk Level of 10 -6 ÷ Unit Risk (μg/L) -1

Mutagenic Mode of Action If the chemical has a mutagenic mode of action, low dose linear extrapolation is used to cal culate the CSF as described above . EPA’s 2005 Guidelines for Carcinogen Risk Assessment (USEPA, 2005b) require that the potential increased cancer r isk due to earlylife exposure be taken into account for chemicals with a mutagenic mode of action . When chemical

- specific data to quantify the increased risk are lacking, Age Dependent Adjustment Factors (ADAFs) are applied to estimate age

- specific unit risks. The total
age- adjusted unit risk is calculated as the sum of the unit risks for each of the three ADAF developmental groups (birth to < 2 yrs; 2 yrs to < 16 yrs; 16 yrs to 70 yrs). TheEPA – OGW DW Protocol for Regulatory Determination 3 April 2014

38 age- adjusted unit risks include a ten -fold adjustment for early l ife (b irth to < 2 yrs ) exposures, a three-fold adjustment for childhood/adolescent (2 yrs to < 16 yrs ) exposures, and no additional adjustment for exposures later in life (16 yrs to 70 yrs) , in conju nction with age- specific drinking water intake values derived from EPA’s 2011 Exposure Factors Handbook (USEPA, 2011a) and the fraction of a 70- year lifetime applicable to each age period . The total age-adjusted unit risk is the upper-bound excess lifetime cancer risk estimated to result from continuous postnatal exposure to a chemical at a concentration of 0.001 mg/L in drinking water. Age

- Adjusted Unit Risk (μg/L) - 1 = ∑(CSF x ADAF x DWI /BWR x CW x F) where:

CSF = The Cancer Slope Factor (mg/kg/day) -1
ADAF = The Age Dependent Adjustment Factor for the age group: birth to two

years (ADAF=10), two years to sixteen years (ADAF=3), and sixteen to seventy years (ADAF=1) DWI /BW R = Drinking Water Intake Body Weight Ratio (DWI /BW R ) expressed as liters per kg body weight for the age group (90 th percentile, consumers only), in L/kg CW = Unit risk concentration in drinking water of 0.001 mg/L (1 μg/L) F = The fraction of a 70- year lifetime applicable to the age period : 2/70 for birth to two year s, 14/70 for two years to sixteen year s, and 54/70 for sixteen years to seventy years)

The cancer HRL , which corresponds to an excess estimated lifetime cancer risk of one in a million (10 -6 ), is calculated by div iding the population risk level by the unit risk:

HRL (μg/L) = Risk Level of 10-6 ÷ Total Age- Specific Unit Risk (μg/L) -1 Non

Linear Mode of Action and Other Exceptions

For carcinogens with an identified non- linear mode of action , the HRL is derived using the RfD approach, in the same manner as non -carcinogens, as described in the next section

. For contaminants that are considered only “possible” human carcinogens (or “Group C,” per the agency’s 1986 Guidelines for Carcinogen Risk Assessment ), the HRL is also generally derived using the RfD approach based on non- cancer effects , along with an additional safety factor of up to 10 to account for possible carcinogenicity.Derivation of an HRL for Non- carcinogens

EPA generally calculates a reference dose (RfD) for those chemicals considered to be non

carcinogenic or not likely to be carcinogenic to humans. An RfD is an estimate of a daily oral exposure to the human population (including sensitive populations or life stage s) that is likely to be without an appreciable risk of deleterious effects during a lifetime. The RfD can be derived from either a no

- observed -adverse- effect level (NOAEL), a lowest -observed-adverse- effect level (LOAEL), or the 95% lower confidence bound on a benchmark dose (BMD), knows as a BMDL

, with uncertainty factors applied to reflect limitations of the data used. In addition, if the critical health endpoint has high quality data associated with exposure for a specific developmental group or period of sensitivity, age-specific drinking water intake to body weight ratio values from the 2011 Exp osure Factors Handbook may be included in deriving an HRL from the RfD (USEPA, 2011a).EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

39 The a gency uses uncertainty factor s (UF s ) to address uncertainty resulting from incompleteness of the toxicological database (e.g., lacking sensitive population data). The i ndividual UFs (usually applied as integers of one, three, or ten) are multiplied together and used to derive the RfD from experimental data. Individual UFs are intended to account for:

(1) Variation in sensitivity among the members of the human population (i. e.,intraspecies variability ). (2) Uncertainty in extrapolating animal data to humans (i.e., interspecies variability). (3) Uncertainty in extrapolating from data obtained in a study with less- than

- lifetime exposure to lifetime exposure (i.e., extrapolating from subchronic to chronic exposure). (4) Uncertainty in extrapolating from a LOAEL rather than from a NOAEL. (5) U ncertainty associated with an incomplete database.

Under the RfD approach, the HRL is calculated as follows:

HRL (mg/L) = [(RfD x BW)/DWI] x RSC

w here :

RfD = Reference Dose BW = Body Weight, assumed to be 70 kg for an adult and 10 kg for a child DWI = Drinking Water Intake, assumed to be 2 L/day (90th percentile) for an adult, and 1 L/day (90 th percentile) for a child RSC = Relative Source Contribution, or the level of exposure b elieved to result from drinking water when compared to other sources (e.g., food, ambient air). In all

cases , a 20 % RSC is used for HRL derivation because (1) HRLs are developed prior to a complete exposure assessment , and (2) 20% is the lowest and most conservative RSC used in the derivation of an MCLG for drinking water.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

40 

## Appendix B

. Health Assessment Data Sources for RD 3
EPA uses health assessments from several EPA and non- EPA designated sources to evaluate health effects for contaminants considered for RD 3

. While EPA health assessments are preferred, non

- EPA health assessments were also considered for RD 3, if the health assessment used comparable methods, standards, and guidelines to an EPA health assessment. The following externally peer

- reviewed health assessments sources c omprise the drinking water health data used to support RD 3 :



### EPA Health Assessments: Integrated Risk Information System (IRIS): ( http://cfpub.epa.gov/ncea/iris/index.cfm?fuseaction=iris.showSubstanceList )

EPA ’ s Integrated Risk Information System (IRIS) is a human health assessment program that compiles and evaluates information on health effects that may resul t from exposure to environmental contaminants. Through the IRIS Program, EPA provides the highest quality science

- based human health assessments to support the a gency’s regulatory activities. The IRIS database contains information on more than 550 chemical substances containing information on human health effects that may result from exposure to various substances in the environment. The IRIS database is prepared and maintained by EPA’s National Center for Environmental Assessment (NCEA) within the Office of Research and Development (ORD).

The heart of the IRIS database is its collection of searchable documents that describe the health effects of individual substances and that contain descriptive and quantitative information in the following categories:

• Non

- cancer effects: Oral reference doses and inhalation reference concentrations (RfDs and RfCs, respectively) for effects known or assumed to be produced through a nonlinear (possibly threshold) mode of action. In most instances, RfDs and RfCs are developed for the noncarcinogenic effects of substances.

• Cancer effects: Descriptors that characterize the weight of evidence for human carcinogenicity, oral slope factors, and oral and inhalation unit risks for carcinogenic effects. Where a nonlinear mode of action is established, RfD and RfC values may be used.

Office of Pesticide Program’s (OPP) REDs, IREDs and TREDs : ( http://iaspub.epa.gov/apex/pesticides/f?p=chemicalsearch:1 ) In 2008, EPA completed a review of older pesticides (those initially registered prio r to November 1984) under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) to ensure that they met current scientific and regulatory standards. This process, called reregistration

, enabled EPA to call in and review supporti ng scientific stud ies, complete human health and ecological risk assessments, and develop risk mitigation measures as needed using current science, transparency, and input from stakeholders and the public. EPA also reassessed existing tolerances (pesticide residue limits in food) to ensure that they met the safety standard established by the Food Quality Protection Act (FQPA) of 1996 . EPA integrated reregistration and tolerance reassessment to most effecti vely accomplish the goals of both programs. When EPA completes its review of a pesticide for reregistration or tolerance reassessment, the agency issues a risk management decision document known as a RED, an IRED, or a TRED. EPAEPA – OGW DW Protocol for Regulatory Determination 3 April 2014

41 publishes Notices of Availability in the Federal Register

.

• REDs (Reregistration Eligibility Deci sions) When EPA completes the review and risk management decision for a pesticide that is subject to reregistration (that is, one initially registered before November 1984), the agency generally issues a Reregistration Eligibility Decision or RED document. The RED summarizes the risk assessment conclusions and outlines any risk reduction measures necessary for the pesticide to continue to be registered in the U.S.

• IREDs (Interim Reregistration Eligibility Decisions) EPA issues an IRED for a pesticide that is undergoing reregistration, requires a reregistration eligibility decision, and also needs a cumulative assessment as a result of FQPA because it is part of a group of pesticides that share a common mechanism of toxicity. The IRED, issued after EPA compl etes the individual pesticide ’s aggregate risk assessment, may initiate risk reduction measures

-- for example, reducing risks to workers or eliminating uses that the registrant no longer wishes to maintain

-- to gain the benefits of these changes before the f inal RED can be issued, following the agency's consideration of cumulative risks.

• TREDs (Reports on FQPA Tolerance Reassessment Progress and [Interim] Risk Management Decisions)

o A TRED may be issued as a document if no changes in the tolerances for a pesticide are required as a result of EPA ’ s review. If tolerance revisions are required, then the TRED may be issued as a Federal Register Notice. EPA issues a TRED for a pesticide that requires tolerance reassessment decisions, but does not require a reregistration eligibility decision at present because: T he pesticide was initially registered after November 1, 1984, and by law is not included within the scope of the reregistration program.

o EPA completed a RED for the pesticide before FQPA was enacted on August 3, 1996.

o T he pesticide is not registered for use in the U.S. but tolerances are established that allow crops treated with the pesticide to be imported from other countries.

Like IREDs, some TREDs will not become final until EPA considers the cumulative risks of all the pesticides in the cumulative group.

O ffice of W ater (OW) Assessments : ( http://water.epa.gov/drink/standards/hascience.cfm )

The agency performs a literature search for studies published after the available health
assessment (listed in Appendix D) is completed to determine if new information suggests a different outcome. The agency collects and evaluates any peer

- reviewed publications identified through the literature search for their impact on the RfD and/or cancer assessment. In cases where the recent data indicates that a change to the existing RfD or cancer assessment is needed and the contaminant is continuing to the Regulatory Determination Assessment Phase ( Phase 3)

, the updated OW assessment, described in the Health Effects Support Document, is prepared and independently peer-reviewed. These documents address the exposure from drinking water andEPA – OGW DW Protocol for Regulatory Determination 3 April 2014

42 other media, toxicokinetics, hazard identification, and dose-response assessment, and provide an overall characterization of risk from drinking water. For the contaminants with low or no

occurrence , refer to the EPA health risk assessments online from OPP or IRIS for additional health effect information.



### Non

- EPA Health Assessments : These non- EPA health assessments were recognized by the agency because of their standardized methods for characterizing health effects data, relevancy to drinking water exposures, and comparability to EPA methods.

Agency for Toxic S ubstances & D isease R egistry (ATSDR): ( http://www.atsdr.cdc.gov/az/a.html )

By Congressional mandate, the Agency for Toxic Substances and Disease Registry (ATSDR) produces “ toxicological profiles ” for hazardous substances found at National Priorities List (NPL) sites. These hazardous substances are ranked based on frequency of occurrence at NPL sites, toxicity, and potential for human exposure. Toxicological profiles are developed from a priority list of 275 substances. The ATSDR toxicological profile succinctly characterizes the toxicologic al and adverse hea lth effects information f or hazardous substances . Each peer

reviewed profile identifies and reviews the key literature that describes a hazardous substance ’ s toxicologic al properties. Other pertinent literature is also presented, but is described in less detail than the key studies.

ATSDR establishes oral minimal risk levels (MRLs) for non

- neoplastic endpoints for acute (14 days or less), intermediate (15 -364 days), and chronic (365 days or more) exposure durations. MRLs for oral chronic exposure are similar to EPA’s RfDs. However, ATSDR and EPA use different approaches when the database is limited to subchronic studies and no adequate chronic study is available. ATSDR derives an intermediate duration MRL that protects against exposures up to 10% of a lifetime, and it does not incorporate an uncertainty factor to account for using a less -than- lifetime study. ATSDR does not perform quantitative cancer assessments or assign f

ormal cancer classifications or descriptors.

The National Academies: ( http://www.nationalacademies.org/ ) The United States National Academies comprises four organizations:

• National Academy of Sciences (NAS)

.

• National Academy of Engineering (NAE).

• Institute of Medicine (IOM)

.

• National Research Council (NRC)

.

The National Academy of Sciences , National Academy of Engineering, Institute of Medicine

, and National Research Council are private, nonprofit instituti ons that provide expert advice to decision makers and the public.

EPA may commission th e National Academies or use previously published reports to advise EPA on available scientific literature, public policy, health assessments , and exposure
assessments. The reports from the National Academies are viewed as being valuable and credibleEPA – OGW DW Protocol for Regulatory Determination 3 April 2014

43 because of the institution ’ s reputation for providing independent, objective, and nonpartisan advice with high standards of scientific and technical quality. Checks and balances are applied at every step in the study process to protect the integrity of the reports and to maintain publ ic confidence in them.

W orld H ealth O rganization (WHO): ( http://www.who.int/water_sanitation_health/dwq/chemicals/en/ )

The W orld H ealth Organization (WHO) Guidelines for Drinking- Water Quality (GDWQ) include facts sheets and comprehensive review documents for many individual chemicals. WHO derives gui deline values for many of these chemicals . For each chemical contaminant or substance considered, a lead institution prepared a back ground document evaluating the risks for human health from exposure to the particular chemical in drinking water. Under the responsibility of the coordinators for a group of chemicals considered in the guidelines, the draft health criteria documents were s ubmitted to a number of scientific institutions and selected experts for peer review. Comments were taken into consideration by the coordinators and authors before the documents were submitted for final evaluation by the experts meetings. A “final task for ce” meeting reviewed the health risk assessments and public and peer review comments and, where appropriate, decided upon guideline values. The guidelines are intended to be used as a basis for the development of national standards that, if

properly implemented, will ensure the safety of drinking water supplies through the elimination, or reduction to a minimum concentration, of constituents of water that are known to be hazardous to health. W HO ’s guideline value is a drinking water concentration that uses different default assumptions than EPA for estimating water concentration from doses, including a 60 kg adult body weight, daily water consumption of 2 L/day, and a default RSC for drinking
water of 10% (unless data is available to derive an RSC) . W HO develops one guideline value that is based on either cancer or non- cancer health effects

.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

44 

## Appendix C. Data Sources for Occurrence

EPA uses data from several sources to evaluate occurrence and exposure forcontaminants considered for regulatory determinations. The following sources comprised the national sources of drinking water occurr ence data available to support determinations:

• Second Unregulated Contaminant Monitoring Regulation (UCMR 2)

.

• First Unregulated Contaminant Monitoring Regulation (UCMR 1)

.

• Unregulated Contaminant Monitoring (UCM) program (Round 1 and 2).

• National Inorganics and Radionuclides Survey (NIRS)

.

All four are national assessments that were administered or overseen by EPA and contribute to EPA’s N ational Contaminant O ccurrence D atabase (NCOD). EPA notes that NCOD was established in response to the SDWA mandate for a national drinking water contaminant occurrence database that would be integrated with the UCMR, CCL, and Regulatory Determination programs. The SDWA Amendment s state that “a determination to regulate...shall be based on the best available public health information, including the occurrence data base established under section 300j- 4(g) of this title.”

In addition to these national sources of occurrence data, th e a gency also evaluates supplemental sources of information on occurrence in drinking water, occurrence in ambient and source water, and information on contaminant use and release. These are mostly national assessments by federal agencies such as EPA and t he United States Geological Survey (USGS), but they also include regional - and s tate -level surveys and some research performed by private institutions.


### National Data Sources (National Drinking Water Data)

Unregulated Contaminant Monitoring Regulation (UCMR) Assessment Monitoring (AM) :

• Designed to provide nationally representative contaminant occurrence data. Conducted by all PWSs serving more than 10,000 people (a “census”), and a statistically designed national sample of 800 PWSs serving 10,000 or fewer people.

• Includes all 50 states, four Territories, and Tribal lands.

• Monitoring is conducted during a continuous 12-month period at each participating system, at a quarterly monitoring frequency for surface water systems and a twice -a- year monitoring freq uency for ground water systems. At least one sample period must be during a specified vulnerable period.

o UCMR1: Monitoring occurred during 2001-2003 and included 12 chemical contaminants.

o UCMR 2: Monitoring occurred during 2008-2010 and included 10 chemical contaminants.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

45 Unregulated Contaminant Monitoring Regulation : Screening Surveys (SS) :

• Monitoring for contaminants that require specialized analytical method technologies not in wide or common use.

o UCMR 1 Screening Survey monitoring was conducted by a statistically selected sample of 300 large and small PWSs. While the statistical design provided for national data, for relatively low occurrence contaminants there was concern that there was too much uncertainty in the results because of the small number of samples. Hence, these data were not used by themselves as a national data source. Screening Survey monitoring was conducted for 13 chemicals for a 12-month period during 2001 and 2002, and for one microbe in 2003.

o UCMR 2 Screening S urvey design was modified to improve its scope. For UCMR 2 monitoring included a census of all systems serving more than 100,000 (approximately 400 PWSs

-- and the largest portion of the national population served by PWSs); and a statistically selected national sample of 32 0 PWSs serving 10,001 to 100,000 people, and 480 PWSs serving 10,000 or fewer people. Screening Survey monitoring was conducted for 15 contaminants for a 12-month period during 2008-2010.

Unregulated Contaminant Monitoring (UCM): Prior to the development of the UCMR, the unregulated contaminant monitoring (UCM) program required public water systems serving more than 500 people to monitor for specified contaminants, during two time periods. There was no requirement to report these data to EPA and individual states maintained these data in different forms and formats. Following a peer

reviewed protocol, the most complete i ndividual state data sets were assembled into a single “national cross- section ” data set that is indicative of contaminant occurrence natio nally.

• Round 1: The final database includes data on 62 contamin ants. Data were collected from 38 states, DC, and the Virgin Islands between 1988 and 1992. Application of the protocol resulted in a national cross

- section with data from 24 states (22,000 PWS s).

• Round 2: The final database includes data on 48 contaminants. These data were collected from 35 states and primacy entities between 1993 and 1997. Application of the protocol resulted in a national cross

- section with data from 20 states (27,000 PWSs).

National Inorganic and Radionuclide Survey (NIRS): NIRS provides d ata on the occurrence of a select set of radionuclides and inorganic chemicals

.

• It provides contaminant occurrence data from 989 community water systems (CWSs) served by ground water sourc es.

• Each of these randomly selected PWSs was sampled a single time between 1984 and 1986. Selection of the PWSs was designed so that the contaminant occurrence results from these PWSs would be representative of national occurrence of contaminants in
groun d water systems.

• The data are from 49 states (there are no data from Hawaii), as well as Puerto Rico.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

46 

### Non

- National Drinking Water Data Sources

Unregulated Contaminant Monitoring Regulation 1 Screening Survey:

• As noted above, UCMR 1 Screening Survey monitoring was conducted by a national sample of 300 large and small PWSs. While the statistical design provided for national data, for relatively low occurrence contaminants there was concern that there was too much uncertainty in the results because of t he small number of samples . Hence, these data were not used by themselves as a national data source. Monitoring was conducted for 13 chemicals for a 12-month period during 2001 and 2002, and for one microbe in 2003.

o The scope of the UCMR 2 Screening Survey was expanded beyond that of UCMR 1 Screening Survey to the point that it could be considered a primary data source, as described above.

Disinfection By

- Product Information Collection Rule (DBP ICR): The DBP ICR r equired public water systems serving at l east 100,000 people to monitor and collect data on disinfection byproducts (DBPs) from July 1997 to December 1998. The DBP data were collected from 296 water systems. The DBP ICR is national in scope, with monitoring sites geographically distributed across the country

, but it is not intended to be statistically representative of the nation.

Individual State s ’ Data Six- Year Review Information Collection Request: The purpose of this ICR wa s to support the national contaminant occurrence and exposure assessments performed under the Six

- Year Review process. EPA analyzes SDWA compliance monitoring data from public water supplies for contaminants with National Primary Drinking Water Regulations (NPDWRs). Data were obtained from compliance monitoring of pu blic water systems. The data were used to construct a national cross -section that would be indicative of national contaminant occurrence. Data sets received from some states also included some limited information on unregulated contaminants that were usefu l for the Regulatory Determination Process.

• Six -Year 1 (2003): EPA reviewed 69 NPDWRs that were established prior to 1997. Data were obtained from 16 states (41,000 PWSs). Data from 1993 to 1997 were used in analyses.

• Six Year 2 (2010 ): EPA reviewed 71 NPD WRs . Data were obtained from 45 states plus Region 8 and Region 9 tribes (132,000 PWSs) . Data collected from 1998 -2005. Six of the states (California, Illinois, North Carolina, South Dakota, Ohio, and Texas) and the Region 9 tribes submitted PWS occurrence data for unregulated contaminants in addition to their data for regulated contaminants in response to the Second Six- Year Review ICR

.

States – Websites : EPA was able to supplement the data on unregulated contaminants obtained during the Six Year 2 process by downloading additional publicly available PWS monitoring data from state

w ebsites . Data were obtained from the Florida and Wisconsin state w ebsites

.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

47 

### Supplemental Drinking Water Data Sources

Community Water System S urvey (CWSS): EPA periodically c ollect s data on the financial and operating characteristics of a random sample of community water systems (CWSs) nationwide. All systems serving more than 500,000 people receive the survey and systems in this size category a re asked questions about concentrations of unregulated contaminants in their raw and finished water. CWSS findings from 2000 and from 2006 have been published.

Consumer Confidence Reports (CCRs): CCRs are a nnual water quality reports that CWSs are req uired to provide to their customers. These reports summarize information on water sources, detected contaminants, and system compliance with EPA drinking water standards.

• CWSs with 15 or more connections or serving at least 25 year-round residents must
pr epare and distribute a CCR to all billing units or service connections every year.

• CWSs serving 100,000 or more residents are also required to post their current CCRs on a publicly accessible Internet site.

EPA reviewed CCRs published by the 26 systems that serve over 1 million customers for unregulated contaminant occurrence information.

Pesticide Data Program (PDP): The goal of the Pesticide Data Program (PDP) Water Monitoring Survey is to collect monitoring data on pesticide residues. The PDP water monitoring survey began in 2001 when Congress allocated money to USDA’s Agricultural Marketing Service ( AMS ) for the purpose of providing these data. The PDP water survey is designed in consultation with EPA to provide data for agricultural use pesticides under evaluation , related to the Food Quality Protection Act ( FQPA ). The sampling frame is designed to provide coverage in regions of interest for at least two years
to re flect the seasonal and climatic variability during growing seasons. PDP works with EPA and American Water Works Association (AWWA ) to identify specific water treatment facilities where monitoring data are needed.

United States Geological Survey Pilot Monitoring Program (USGS PMP): Initia ted in 1999, PMP provides information on pesticide concentrations in drinking water. This study focused on small drinking water supply reservoirs in areas with high pesticide use to test and refine the sampling approach in areas where pesticides are probably present. Sampling sites represent a variety of geographic regions, as well as different cropping patterns.

• These 12 sites were located in: California, Indiana, Ohio, Oklahoma, Louisiana, Missouri, South Carolina, South Dakota, New York, North Carolina, Pennsylvania, and Texas.

• Samples were collected quarterly throughout the year and at weekly or biweekly intervals following the primary pesticide -application periods.

• Water samples were collected from the raw -water intake and from the finished drinkingwater tap prior to entering the distribution system. At some sites, samples were also collected at the reservoir outflow.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

48 Environmental Working Group (EWG): EWG assembled a database of 20 million drinking water quality tests performed by water utilities since 2004. EWG obtained tap water testing data from state water offices, which had collected the results from the utilities as part of their primacy oversight and enforcement of state and federal water quality standards. The data came from approximately 48,000 PWS s in 45 states and the District of Columbia. Among the contaminants detected were 202 unregulated chemicals

. 

### Supplemental Ambient /Source Water Data Sources

USGS National Water Quality Assessment Program (NAWQA): USGS instituted the National Water Quality Assessment program in 1991 to examine ambient water quality status and trends in the United S tates

.

• The program’s sampling approach is not statistically designed (does not involve random sampling).

• Cycle 1 monitoring took place between 1991 and 2001. (Cycle 1 data were used in CCL 3; RD 3 supplemented these data with information from special USGS reports that may have also used some additional data from other programs or from the early years of NAWQA Cycle 2.)

• Data from over 6

, 400 surface water and 7 ,000 ground water sampling points (60% of the nation’s drinking water and water used for agriculture and industry).

• P esticides, nutrients, VOCs, trace elements, and radionuclides

.

• Special USGS reports included:

o Source Water Survey (2001): A netw ork of 25 ground water and 49 surface water sources of public drinking water supply in 25 states and Puerto Rico were sampled and analyzed for 100 emerging contaminants.

o Ground Water Survey (2000): Water samples were collected from a network of 47 ground wate r sites across 18 states

. These samples were analyzed for 65 emerging contaminants. Site selection focused on a variety of geohydrologic areas suspected to be susceptible to contamination from either animal or human wastewaters and were in aquifers not necessarily used as a source of drinking water. The network consisted of 42 wells, 3 springs, and 2 sumps.

o Stream Survey (1999-2000): Water samples were collected from a network of 139 streams across 30 states during 1999 and 2000. Site selection focused on streams considered to be susceptible to contamination ; selected sites represent a wide variety of hydrogeologic, climatic, and land- use settings across the United States.

EPA Storage and Retrieval database (STORET): Th is EPA database c ontains raw biological, chemical, and physical data on surface and ground water collected by federal, state, and local agencies, Indian tribes, volunteer groups, academics, and others. Data co ntained in STORET are primarily for ambient water but they also include

some drinking water data

. USGS National Reconnaissance of Emerging Contaminants (NREC): For CCL 3 , the USGS provided EPA with data from various reconnaissance studies looking at the occurrence of emerging contaminants in surface waters and ground waters. The da taEPA – OGW DW Protocol for Regulatory Determination 3 April 2014

49 represent sites from over 30 states, and include analyses for over 124 contaminants.



### Production/Use/Release Data Sources

Chemical Update System/Inventory Update Rule (CUS IUR): The IUR regulation under the Toxic Substances Control Act (TSCA) requires manufacturers and importers of certain chemical substances included on the TSCA Chemical Substance Inventory to report site and manufacturing information for chemicals manufactured (including imported) in amounts of 25,000 pounds or greater at a single site. Additional information on domestic processing and use must be reported for chemicals manufactured in amounts of 300,000 pounds or more at a single site. Prior to the 2003 amendments (i.e., reporting from 2002 or earlier), information was collec ted for only organic chemicals that were manufactured (including imported) in amounts of 10,000 pounds or more, and was limited to more basic manufacturing information such as production volume.

EPA Office of Pesticide Program s (OPP) Reregistration Documen ts : All pesticides sold or used in the United States must be registered by EPA

. Because of advances in scientific knowledge, the law requires that pesticides which were first registered years ago be reregistered to ensure that they meet today’ s more string ent standards. In evaluating pesticides for reregistration, EPA obtains and reviews various data and studies from pesticide producers, describing the human health and environmental effects of each pesticide.

Office of Pesticide Programs Estimated Concentrations: EPA OPP used modeling to de velop estimated concentrations for acute and chronic exposure scenarios involving surface water and ground water. The estimated concentrations were developed using the Pesticide Root Zone Model/Exposure Analysis Modeling System (PRZM/EXAMS) and Screening Concentrations in Ground Water (SCI

- GROW) model.

National Center for Food and Agricultural Policy (NCFAP): NCFAP is a p rivate non- profit institution that maintain ed a national pesticide use database. Annual pesticide use estimates for circa 1992 and 1997 are base d on state level commercial agricultural usage patte rns for 1990-1993 and 1995-1998 , and state level crop acreage for 1992 and 1997 (collected by USDA). The d atabase contains estimates of pounds applied and acres treated in each state for 220 active ingredients and 87 crops.

• The m ajority of chemicals monitored are herbicides, but it also contains fungicides and insecticides.

• The database o nly includes applications of pesticides to cropland. It d oes n ot include non

bearing orchards or vineyards or governmental area-wide eradication programs.

• The d atabase is compiled from a wide variety of s ources, thus there is n o way to determine the accuracy of any of the estimates. When data for particular states a nd crops are unavailable, as they are in many cases, values are assigned on the basis of data from a nearby state.

USGS Pesticide Use Maps: USGS produces maps of pesticide use for compounds used in US crop production. USGS combines NCFAP s tate

- based pesticide use coefficients for 87 crops with county-level cropEPA – OGW DW Protocol for Regulatory Determination 3 April 2014

50 acreages obtained from the Census of Agriculture. Th e resulting maps show the distribution of average annual pesticide use. Map resolution is based at the county level.

Toxics Release Inventory (TRI): Established in 1987 , TRI requires facilities to report , to both EPA and the s tates , annual information on toxic chemical releases from facilities that meet certain reporting criteria.

• Not all facilities are required to report all releases. Facilities are required to report releases if they manufacture or process more than 25,000 pounds or use more than 10,000 pounds.

• Reporting requirements have changed over time (e.g., reporting thresh olds have decreased); this creates the potential for misleading data trends over time.

• TRI data are meant to reflect releases and should not be used to estimate general public
expo sure to a chemical

.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

51 

## Appendix D

. Summary of Phase 1 : Data Availability
See attachment. 

## Appendix E. Summary of Phase 2 Data Evaluation
See attachment. 

## Appendix F. Summary of Phase 3 Regulatory Determination Assessments

See attachment.EPA – OGW DW Protocol for Regulatory Determination 3 April 2014

52 

## Appendix G

. Evaluation of Statutory Criterion #3 Statutory Criterion #3 requires th at in the sole judgment of the Administrator, regulation of a contaminant presents a meaningful opportunity for health risk reduction for persons served by PWSs . EPA evaluates the population exposed at the health level of concern along with several other factors to determine if regulation presents a meaningful opportunity for health risk reduction. The EPA Administrator may consider the following factors in evalu ating statutory criterion #3:

• Based on the occurrence information for statutory criterion #2 (and the potential number of systems impacted), what is the national population exposed or served by systems with levels > HRL and 1⁄2 HRL (provide actual and estimated # and %)?

• What is the nature of the health effect(s) identified in statutory criterion #1 and are there sensitive populations that may be impacted (either qualitative or quantitative)?

• For non-carcinogens, are there other sources of exposure that should be considered (i.e., what is the relative source contribution)?

• What is the geographic distribution of occurrence (e.g., local, regional, national)?

• Are there any uncertainties and/or limitations in the health and occurrence information or analyses tha t should be considered?

• What other factors or other pieces of information should be considered that may have direct bearing on any decision to regulate the contaminant (e.g., treatment, analytical methods, etc.)?

After evaluating these factors, if the Administrator determines that there is a meaningful opportunity to reduce risk by regulating the contaminant in drinking water, then the agency answers “yes” to the third statutory criterion.April 2014 Page 1 of 3

CASRN Common Name Occurrence Data Type Best Available Occurrence Data Source Primary Health Effects Data Source 9 Health Assessment Status 10 Place on Short List for Phase 2

96184 1,2,3-Trichloropropane 1 National DW UCM IRIS (2009) 11 Available Assessment Yes 1

34256821 Acetochlor 2 National DW UCMR1 (AM) OPP TRED (2006) 11 Available Assessment Yes 2

187022113 Acetochlor ethanesulfonic acid (ESA) 2 National DW UCMR2 OPP TRED (2006) Available Parent Assessment Yes 2
184992444 Acetochlor oxanilic acid (OA) 2 National DW UCMR2 OPP TRED (2006) Available Parent Assessment Yes 2
142363539 Alachlor ethanesulfonic acid (ESA) 2 National DW UCMR2 OPP RED (1998) Available Parent Assessment Yes 2
171262172 Alachlor oxanilic acid (OA) 2 National DW UCMR2 OPP RED (1998) Available Parent Assessment Yes 2
60515 Dimethoate National DW UCMR2 OPP IRED (2007) Available Assessment Yes 98953 Nitrobenzene 1 National DW UCMR1 (AM) IRIS (2009) Available Assessment Yes 1

62759 N-nitrosodimethylamine (NDMA) 2 National DW UCMR2 Draft OW Health Assessment (2010) 11 Available Assessment Yes 2

56070167 Terbufos sulfone 2 National DW UCMR2 OPP RED (2006) Available Parent Assessment Yes 2

7440622 Vanadium National DW NIRS Draft ATSDR (2009) 11 Assessment in Process (ATSDR) Yes 630206 1,1,1,2-Tetrachloroethane 1 National DW UCM IRIS RfD (1987) Available Assessment Yes 1
99650 1,3-Dinitrobenzene National DW UCMR2 IRIS RfD (1988) Available Assessment Yes 51218452 Metolachlor 2 National DW UCM OPP RED (1995) Available Assessment Yes 2

171118095 Metolachlor ethanesulfonic acid (ESA) 2 National DW UCMR2 OPP RED (1995) Available Parent Assessment Yes 2

152019733 Metolachlor oxanilic acid (OA) 2 National DW UCMR2 OPP RED (1995) Available Parent Assessment Yes 2
2212671 Molinate National DW UCMR1 (AM) IRIS (1988) Available Assessment Yes 7439987 Molybdenum National DW NIRS NAS (2001)/IRIS (1991) Available Assessment Yes 55185 N-Nitrosodiethylamine (NDEA) 2 National DW UCMR2 IRIS (1987) Available Assessment Yes 2

621647 N-Nitroso-di-n-propylamine (NDPA) 2 National DW UCMR2 IRIS (1987) Available Assessment Yes 2

930552 N-nitrosopyrrolidine (NPYR) 2 National DW UCMR2 IRIS (1987) Available Assessment Yes 2

74839 Methyl bromide (Bromomethane) National DW UCM OPP (2006) 11 Available Assessment Yes 121824 RDX National DW UCMR2 IRIS (1988) Assessment in Process (IRIS) Yes 7440484 Cobalt National DW NIRS ATSDR (2004) Available Assessment Yes 1634044 Methyl tert-butyl ether (MTBE) National DW UCMR1 (AM) OEHHA(CA) (1999) Assessment in Process (IRIS) Yes 7440246 Strontium National DW NIRS IRIS (1992) Available Assessment Yes 75343 1,1-Dichloroethane 1 National DW UCM OEHHA(CA) (2003) No Assessment No 1

16655826 3-Hydroxycarbofuran 3 National DW UCM OPP IRED (2006) [parent] No Assessment No 3
74873 Chloromethane (Methyl chloride) National DW UCM RAISHE (1981) No Assessment No 7440564 Germanium National DW NIRS RTECS No Assessment No 74975 Halon 1011 (bromochloromethane) National DW UCM OW Health Advisory (1989) No Assessment No 103651 n-Propylbenzene National DW UCM RTECS No Assessment No 135988 sec-Butylbenzene National DW UCM RTECS No Assessment No 13494809 Tellurium National DW NIRS Supplemental Data (1988) No Assessment No 123911 1,4-Dioxane Non-National DW State data > 1/2HRL IRIS (2010) 11 Available Assessment Yes 30560191 Acephate Non-National DW State data > 1/2HRL OPP RED (2006) Available Assessment Yes 107028 Acrolein Non-National DW State data IRIS (2003) Available Assessment No 741582 Bensulide Non-National DW State data OPP RED (2006) Available Assessment No 133062 Captan Non-National DW State data OPP RED (2004) Available Assessment No 14866683 Chlorate Non-National DW DBP ICR > 1/2HRL/DBP OPP RED (2006) Available Assessment Yes 141662 Dicrotophos Non-National DW State data OPP RED (2006) Available Assessment No 298044 Disulfoton 4 Non-National DW UCMR1 (SS) & other OPP RED (2006) Available Assessment Yes 4

330541 Diuron 4 Non-National DW UCMR1 (SS) & other OPP RED (2003) Available Assessment Yes 4
13194484 Ethoprop Non-National DW Supplemental OPP RED (2006) Available Assessment No 107211 Ethylene glycol Non-National DW State data IRIS (1987) Available Assessment No 96457 Ethylene thiourea (Maneb) Non-National DW Supplemental OPP RED (2005) Available Assessment No 22224926 Fenamiphos Non-National DW State data OPP IRED (2002) Available Assessment No 10265926 Methamidophos Non-National DW State data OPP RED (2006) Available Assessment No 301122 Oxydemeton-methyl Non-National DW Supplemental OPP RED (2006) Available Assessment No CHEMICALS 

## Appendix D. Summary of Phase 1: Data AvailabilityApril 2014 Page 2 of 3

CASRN Common Name Occurrence Data Type Best Available Occurrence Data Source Primary Health Effects Data Source 9 Health Assessment Status 10 Place on Short List for Phase 2 CHEMICALS 

## Appendix D. Summary of Phase 1: Data Availability

42874033 Oxyfluorfen Non-National DW Supplemental OPP RED (2002) Available Assessment No 1763231 Perfluorooctane sulfonic acid (PFOS) Non-National DW Supplemental > 1/2HRL OW Provisional HA (2009) Assessment in Process (OW) Yes 335671 Perfluorooctanoic acid (PFOA) Non-National DW Supplemental > 1/2HRL OW Provisional HA (2009) Assessment in Process (OW) Yes 52645531 Permethrin Non-National DW State data OPP RED (2009) Available Assessment No 41198087 Profenofos Non-National DW Supplemental OPP RED (2006) Available Assessment No 107534963 Tebuconazole Non-National DW Supplemental OPP RED (2008) Available Assessment No 13071799 Terbufos 2 Non-National DW UCMR1 (SS) & other OPP RED (2006) Available Assessment Yes 2
78488 Tribufos Non-National DW Supplemental OPP RED (2006) Available Assessment No 50471448 Vinclozolin Non-National DW Supplemental OPP RED (2000) Available Assessment No 137304 Ziram Non-National DW State data OPP RED (2003) Available Assessment No 71363 1-Butanol Non-National DW State data IRIS (1988) Available Assessment No 319846 alpha-Hexachlorocyclohexane Non-National DW Supplemental IRIS (1987) Available Assessment No 100447 Benzyl chloride Non-National DW Supplemental IRIS (1989) Available Assessment No 50000 Formaldehyde Non-National DW DBP ICR IRIS (1990) Assessment in Process (IRIS) No 86306 N-Nitrosodiphenylamine (NDPhA) 2,5 Non-National DW State data IRIS (1987) Available Assessment Yes 2,5
57910 17alpha-estradiol 7 Non-National DW Supplemental WHO (1999) No Assessment No 7
75070 Acetaldehyde Non-National DW DBP ICR RTECS No Assessment No 64285069 Anatoxin-a Non-National DW Supplemental Supplemental Data (1981) No Assessment No 62533 Aniline Non-National DW State data RAISHE No Assessment No 25013165 Butylated hydroxyanisole Non-National DW Supplemental RTECS No Assessment No 143545908 Cylindrospermopsin Non-National DW Supplemental Supplemental Data (2006) No Assessment No 517099 equilenin 7 Non-National DW Supplemental WHO (1999) No Assessment No 7
474862 equilin 7 Non-National DW Supplemental WHO (1999) No Assessment No 7
114078 Erythromycin 8 Non-National DW Supplemental WHO (2006) No Assessment No 8
50282 Estradiol (17-beta estradiol) Non-National DW Supplemental OEHHA(CA) No Assessment No 50271 estriol 7 Non-National DW Supplemental WHO (1999) No Assessment No 7
53167 estrone 7 Non-National DW Supplemental WHO (1999) No Assessment No 7
57636 Ethinyl Estradiol (17-alpha ethynyl estradiol) Non-National DW Supplemental Supplemental Data (1981) No Assessment No 75456 HCFC-22 Non-National DW Supplemental RTECS No Assessment No 110543 Hexane Non-National DW State data RAISHE No Assessment No 72333 Mestranol Non-National DW Supplemental Supplemental Data (1981) No Assessment No 101043372 Microcystin-LR Non-National DW Supplemental Supplemental Data (2006) No Assessment No 68224 Norethindrone (19-Norethisterone) Non-National DW Supplemental Supplemental Data No Assessment No 106990 1,3-Butadiene 1 Release TRI OEHHA(CA) (2000) No Assessment No 1
109864 2-Methoxyethanol Release TRI RAISHE No Assessment No 107186 2-Propen-1-ol Release TRI IRIS (1986) Available Assessment No 101779 4,4'-Methylenedianiline Release TRI OEHHA(CA) (2001) No Assessment No 60355 Acetamide Release TRI OEHHA(CA) No Assessment No 110429624 Clethodim Use NCFAP OPP RED (2008) Available Assessment No 80159 Cumene hydroperoxide Release TRI RTECS No Assessment No 55290647 Dimethipin Release TRI OPP RED (2005) Available Assessment No 75218 Ethylene oxide Release TRI OEHHA(CA) (2000) No Assessment No 302012 Hydrazine Release TRI IRIS (1989) Available Assessment No 67561 Methanol Release TRI IRIS (1988) Assessment in Process (IRIS) No 55630 Nitroglycerin Release TRI RTECS Available Assessment No 872504 N-Methyl-2-pyrrolidone Release TRI WHO (2001) Available Assessment No 95534 o-Toluidine Release TRI OEHHA(CA) (1997) No Assessment No 75569 Oxirane, methyl- Release TRI OPP RED (2006) Available Assessment No 91225 Quinoline Release TRI IRIS (2001) Available Assessment No 112410238 Tebufenozide Use NCFAP OPP RED (1999) Available Assessment NoApril 2014 Page 3 of 3

CASRN Common Name Occurrence Data Type Best Available Occurrence Data Source Primary Health Effects Data Source 9 Health Assessment Status 10 Place on Short List for Phase 2 CHEMICALS 

## Appendix D. Summary of Phase 1: Data Availability

59669260 Thiodicarb Release TRI OPP RED (1998) Available Assessment No 23564058 Thiophanate-methyl Release TRI OPP RED (2004) Available Assessment No 26471625 Toluene diisocyanate Release TRI OEHHA(CA) (2000) No Assessment No 121448 Triethylamine Release TRI RTECS No Assessment No 76879 Triphenyltin hydroxide (TPTH) Release TRI OPP RED (1999) Available Assessment No 51796 Urethane Release TRI Supplemental Data (2005) No Assessment No 14797730 Perchlorate National DW UCMR1 (AM) IRIS (2005) Regulation Determinaton made in Feb 2011 No

Enterovirus 5 National DW GWR EA Scientific Literature Available Assessment No 5
Adenovirus 5 Non-National DW Misc 6 Scientific Literature Available Assessment No 5,6
Caliciviruses 5 Non-National DW Misc 6 Scientific Literature Available Assessment No 5,6 Legionella pneumophila 5 Non-National DW Misc 6 Scientific Literature Available Assessment No 5,6 Mycobacterium avium 5 Non-National DW Misc 6 Scientific Literature Available Assessment No 5,6 Naegleria fowleri 5 Non-National DW Misc 6 Scientific Literature No Assessment No 5,6 Campylobacter jejuni No Data Scientific Literature No Assessment No Escherichia coli (0157) No Data Scientific Literature Available Assessment No Helicobacter pylori No Data Scientific Literature Available Assessment No Hepatitis A virus No Data Scientific Literature Available Assessment No Salmonella enteric No Data Scientific Literature No Assessment No Shigella sonnei No Data Scientific Literature No Assessment No

Have National DW Data (i.e. UCMR1(AM), UCMR2, UCM1/2, or NIRS) and No Health Assessment Have Non-National DW Data (e.g. UCMR1(SS), State Data, DBP-ICR, or supplemental DW and source water data such as PDP, PMP, NREC, and/or targeted surveys or localized state/federal monitoring studies) and Available or In Process Health Assessment Have Non-National DW Data (e.g. UCMR1(SS), State Data, DBP-ICR, or supplemental DW and source water data such as PDP, PMP, NREC, and/or targeted surveys or localized state/federal monitoring studies) and no Health Assessment Do not have National or Non-National Finished Water Data Not within scope of CCL RD3 since Regulatory Determination made in February 2011 5 Does not have a widely available analytical method for occurrence monitoring. 4 UCMR 1 SS is a statistically defined, national sample of PWSs. Because this survey only includes 300 systems, the Agency identified and compiled additional supplemental data to compliment the UCMR 1 SS data for these contaminants that proceed to the Phase 2 evaluation for further evaluation.

8 Health assessment did not use a standard US EPA methodology (i.e., antibiotic)

LEGEND Have National DW Data (i.e. UCMR1(AM), UCMR2, UCM1/2, or NIRS) and Available or In Process Health Assessment 6 Misc - The evaluation of the pathogens utilized miscellaneous reports from CDC and the scientific literature to try to characterize occurrence; see the CCL 3 support documents for details

7 Metabolite of 17-beta estradiol; no independent health assessment is available

10 The "Primary Health Effects Data Source" must have an externally peer-reviewed health assessment from designated EPA source (i.e., IRIS, OPP, or OW) to be considered an "Available Assessment" or an externally peerreviewed health assessment with an oral RfD/Cancer Slope Factor and comparable EPA methods from a designated non-EPA source (i.e., ATSDR, NAS, or WHO) to be considered an "Available Asessment." 9 A literature search was conducted to determine if any health assessments had been completed from a designated EPA or non-EPA data sources since the publication of the Final CCL 3 Information Sheets in August 2009, if not, the health effects data sources compiled during CCL 3 were used as the "Primary Health Effects Data Source" for RD 3

11 A designated EPA or non-EPA health assessment has been updated or completed since the publication of the Final CCL 3 Information Sheets (August 2009). PATHOGENS

3 Available parent (Carbofuran) assessment does not contain a chronic/subchronic RfD; all tolerances for the parent were cancelled in May 2009; therefore this compound does not proceed to Phase 2. 1 Component of cVOC contaminant group and is being evaluated in another regulatory process

2 Component of contaminant group and will be further evaluated in phase 2Phase 2 of Protocol for Regulatory Determination 3 April 2014

1 of 84 

## Appendix E. Summary of Phase 2 : Data Evaluation

Contaminant Profile Summary of Analyses, Results, and Status (Note: the HRLs used in Phase 2 are draft values and are not final until Regulatory Determinations are complete) No. Contaminant/Background Health Effect Findings Initial Occurrence Findings Phase 2 Outcome & Rationale

1. 1,1,1,2

- Tetrachloroethane

• CASRN = 630206

• Substance Key = 9105

• A halogenated alkane

• Used as a chemical intermediate

Production / Release Data

TRI

- Release 20 10

• Surface water = 0 lbs/yr ( 0 states)

• Total = 3,565 lbs/yr ( 5 states)

TRI

- Release 200 8

• Surface water = 0 lbs/yr ( 0 states)

• Total = 2,904 lbs/yr (4 states)

TRI

- Release 2006

• Surface water = 0 lbs/yr (0 states)

• Total = 4,358 lbs/yr (6 states)

TRI

- Release 2004

• Surface water = 36 lbs/yr (2 Critical Health Endpoint

• Mineralization of the kidneys (male), hepatic clear cell change (female) (NTP, 1983)

• LOAEL = 89.3 mg/kg

- day

• UF = 3,000

• RfD = 0.03 mg/kg

- day

• Non

- cancer HRL = 210 μg/L

Health Assessment Status

• IRIS ( 1987 )

• Possible human carcinogen, group C (1986 cancer guidelines)

• IRIS completed a comprehensive review of toxicological studies ; a change to the RfD was not

warra nted (August 2006)

Sensitive Populations/Lifestages

• None identified Analyzed using HRL of 210 μg/L

National Drinking Water Data

NCOD/UCM Round 1 Finished Water (1988

- 1992)

• MRL unavailable (min detect = 0.06 μg/L)

• No detects >1⁄2HRL or >HRL

• % samples w/ detects = 0.08% (43 of 56,734)

• % PWSs w/ detects = 0.18% (31 of 16,956)

• Median detect = 0.59 μg/L

• 99%ile detect = 8.28 μg/L

• Max detect = 9.2 μg/L

NCOD/UCM Round 2 Finished Water (1993

- 1997)

• MRL unavailable (min detect = 0.2 μg/L)

• No detects >1⁄2HRL or >HRL

• % samples w/ detects = 0.07% (70 of 97,950)

• % PWSs w/ detects = 0.21% (51 of 24,127)

• Median detect = 0.5 μg/L

• 99%ile detect = 7.58 μg/L

• Max detect = 18.0 μg/L

Non -N ational Drinking Water Data

State Drinking Water Data (1983

- 2009)

• No detects >1⁄2HRL or >HRL

• % systems w/ detects = Referred to CVOC for evaluation. After evaluation of group information, EPA will decide whether to include in CVOC group and evaluate for regulatory determination.Phase 2 of Protocol for Regulatory Determination 3 April 2014

2 of 84 states)

• Total = 12,088 lbs/yr (7 states)

CUSIUR Production Data

• >1M

- 10M lbs/yr (1998, 2002)

Fate / Transport

• Physical and chemical properties give contrary indications about expected mobility in water

• Persistent in the environment (biodegrades sometimes/recalcitrant ); BST is the highest category available to be awarded to a recalcitrant contaminant ( CCL CIS ) o CA: 0.15% (6 of 4,037)

o FL: 3.70% (1 of 27)

o IL: Not detected from 2 systems

o NC: 0.52% (13 of 2,493)

o OH: 0.04% (1 of 2,533)

o R9 Tribes: Not detected from 285 systems

o SD: Not detected from 281 systems

o TX: Not detected from 5,660 systems

o WI ’83

- ’99: Not detected from 1,929 systems

o WI ’00

- ’09: Not detected from 1,120 systems

Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (2006

- 2007)

• Not detected in 4 CWSs in NY

EWG (2004

- 2009)

• 18 PWSs from 11 states w/ detects, no detects >1⁄2HRL or >HRL

Supplemental Ambient/Source Water Data

NAWQA Ambient Water (1992

- 2001)

• MRLs variable (0.03 - 0.2 μg/L)

• No SW detects in 1,397 samples from 182 sites

• No GW detects >1⁄2HRL or >HRL

• % GW samples w/ detects = 0.09% (4 of 4,543)

• % GW sites w/ detects = 0.10% (4 of 4,127)

• Median detect = 0.0275 μg/L

• 99%ile detect = 0.0644 μg/L

• Max detect = 0.0644 μg/L

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 1 9 states

• No detects >1⁄2HRL or >HRLPhase 2 of Protocol for Regulatory Determination 3 April 2014

3 of 84 • % GW samples w/ detects = 43.67 % ( 1,135 of 2,599 )

• % SW samples w/ detects = 3 9. 46 % (2 64 of 6 69 )

• % GW sites w/ detects = 37.31 % ( 400 of 1,072 )

• % SW sites w/ detects = 14.18 % ( 20 of 1 41 )

• Median detect = 0 μg/L

• 90%ile detect = 0.5 μg/L

• Max detect = 42 μ g/L
1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

NAWQA Domestic Well Water Quality (1991

- 2004)

• Not detected in 2,268 samples

NAWQA National Focused and Historic VOC Study (1985

- 2001)

• No detections at reporting level of 0.2 μg/L

NAWQA Quality of Public Supply Wells (1993

- 2007; Toccalino et al.)

• MRL = 0.015 - 0.2 μg/L

• No detects >1⁄2HRL or >HRL

• % samples w/ detects = 0.36% (3 of 832)

USGS CWSs Drawing from Streams and Groundwater (2002

- 2005)

• Not detected

NAWQA Carbonate Aquifer Study (1993

- 2005)

• Not detected in 793 samples

USGS VOCs in Highway Runoff

• Not detected

Occurrence summary and/or other information:

• Low percentage of detects in UCM1/2 as well as more recent state and ambient water data

2. 1,2,3

- Trichloropropane

• CASRN = 96184

• Substance Key = 3817 Critical Health Endpoint

• Cancer ( multi

- site tumors ) (NTP, 1993) Analyzed using HRL of 0.0004 μg/L

Referred to CVOC for evaluation.Phase 2 of Protocol for Regulatory Determination 3 April 2014

4 of 84 • A halogenated alkane

• Chemical intermediate, also has been used as a paint and varnish remover, solvent, and degreasing agent

Production / Release Data

TRI

- Release 20 10

• Surface water = 369 lbs/yr ( 1 state )

• Total = 3,503 lbs/yr ( 3 states)

TRI

- Release 200 8

• Surface water = 187 lbs/yr ( 1 state )

• Total = 1,557 lbs/yr ( 3 states)

TRI

- Release 2006

• Surface water = 416 lbs/yr (1 state)

• Total = 2,025 lbs/yr (3 states)

TRI

- Release 2004

• Surface water = 282 lbs/yr (1 state)

• Total = 9,053 lbs/yr (2 states)

CUSIUR Production Data

• >10M

- 50M lbs/yr (1998)

• >1M

- 10M lbs/yr (2002) • CSF = 30 (mg/kg

- day) -1

• Cancer HRL = 0.0004 μg/L (with ADAF)

Non

- Cancer Health Effect



### • Increased absolute liver weight in male rats (NTP, 19 9 3)

• UF = 300

• RfD = 0.00 4 mg/kg

- day

• Non

- cancer HRL = 30 μg/L

Health Assessment Status

• Update d since CCL3

o IRIS (2009)

Sensitive Populations/Lifestages

• Fetuses/infants/children

• Individuals with liver or kidney problems National Drinking Water Data

NCOD/UCM Round 1 Finished Water (1988

- 1992)

• MRL unavailable (min detect = 0.10 μg/L)

• All detects >1⁄2HRL and >HRL

• % samples w/ detects >HRL = 0.13% (76 of 57,205)

• % PWSs w/ detects >HRL = 0.25% (44 of 17,392)

• Median detect = 0.92 μg/L

• 99%ile detect = 90.1 μg/L

• Max detect = 112 μg/L

NCOD/UCM Round 2 Finished Water (1993

- 1997)

• MRL unavailable (min detect = 0.03 μg/L)

• All detects >1⁄2HRL and >HRL

• % samples w/ detects >HRL = 0.02% (23 of 97,955)

• % PWSs w/ detects >HRL = 0.08% (19 of 24,088)

• Median detect = 0.5 μg/L

• 99%ile detect = 2,347 μg/L

• Max detect = 3,000 μg/L

Non -N ational Drinking Water Data

State Drinking Water Data (1983

- 2009)

• All detects >1⁄2HRL and >HRL

• % systems w/ detects >HRL =

o CA: 3.99% (157 of 3,939)

o FL: 3.70% (1 of 27)

o IL: 66.67% (4 of 6)

o NC: 0.20% (5 of 2,493)

o OH: 0.04% (1 of 2,532)

o R9 Tribes: 0.72% (2 of 279)

o SD: 0.36% (1 of 281)

o TX: 0.09% (5 of 5,660)

o WI ’83

- ’99: 0.60% (11 of 1,826)

o WI ’00

- ’09: 0.09% (1 of 1,123) After evaluation of group information, EPA will decide whether to include in CVOC group and evaluate for regulatory determination.Phase 2 of Protocol for Regulatory Determination 3 April 2014

5 of 84 • 500k – <1 M lbs/yr (2006)

Fate / Transport

• Expected to be mobile in water and soil, based on physical and chemical properties

• Biodegradation is not expected to be significant. Expected to volatilize from surface water and from wet and dry soils. Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (2006

- 2007)

• Detected in 1 CWS; max detect = 2.2 μg/L, >HRL

CWSS (2006)

• % PWSs w/ detects = 1.1% (1 of 94); max detect = 400 μg/L, >HRL

EWG (2004

- 2009)

• At least 130 PWSs from 11 states w/ detects >HRL

NJDEP (1999

- 2004)

• Exceedances of health

- based drinking water guidance value

(presumably 0.005 μg/L):

o At 1.1% of private wells (30 of 2,640)

o At 4.2% of CWSs (11 of 260)

Supplemental Ambient/Source Water Data

NAWQA Ambient Water (1992

- 2001)

• MRLs variable (most within 0.07 – 0.2 μg/L)

• All GW and SW detects >1⁄2HRL and >HRL

• % GW samples w/ detects >HRL = 1.06% (48 of 4,544)

• % SW samples w/ detects >HRL = 0.43% (6 of 1,397)

• % GW sites w/ detects >HRL = 0.97% (40 of 4,127)

• % SW sites w/ detects >HRL = 1.65% (3 of 182)

• Median detect = 0.4 μg/L

• 99%ile detect = 2.92 μg/L

• Max detect = 2.92 μg/L

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 19 states

• All SW detects >1⁄2HRL and >HRL

• % GW samples w/ detects = 57.26 % ( 1,850 of 3

, 231 )Phase 2 of Protocol for Regulatory Determination 3 April 2014

6 of 84 • % GW samples w/ detects > 1⁄2 HRL = 1.18 % (38 of 3,231 )

• % GW samples w/ detects >HRL = 1.18% (38 of 3,231)

• % SW samples w/ detects >HRL = 38.19% (241of 631)

• % GW sites w/ detects = 42.38 % ( 448 of 1, 057 )

• % GW sites w/ detects > 1⁄2 HRL = 3.31 % (3 5 of 1, 057 )

• % GW sites w/ detects >HRL = 3.31% (35 of 1,057)

• % SW sites w/ detects >HRL = 14.93% (20 of 134)

• Median detect = 0 μg/L

• 90%ile detect = 0.2 μg/L

• Max detect = 10 μg/L
1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

NAWQA National Focused and Historic VOC Study (1985

- 2001)

• MRL = 0.2 μg/L

• Random Survey (1999

- 2001): detected in 0.1% of CWSs (1 of 954); max conc. = 0.31 μg/L, >HRL

• Focused Survey (1999

- 2001): at 134 CWSs; max conc . = 0.09 μg/L, >HRL

• Historical Monitoring (1985

- 1995): At 264 urban wells, max conc. = 1.1 μg/L (>HRL); at 1,729 rural wells; max conc. = 0.2 μg/L; >HRL

NAWQA Rural and Domestic Wells (1986

- 1999)

• MRL = 0.2 μg/L

• % samples w/ detects = 0.6% (10 of 1,615); max detect = 2.1 μg/L, >HRL

NAWQA Quality of Public Supply Wells (1993

- 2007; Toccalino et al.)

• MRL = 0.06 - 0.2 μg/L

• All detects >HRL

• % samples w/ detects >HRL = 1.20% (10 of 832)

Occurrence summary and/or other information:

• High degree of uncertainty in national data (UCM1/2); all detections are 250 times higher than HRL due to detection limit; likely more occurrence >HRL that is undetected

• Some recent state (e.g. CA) data indicate that it is potentiallyPhase 2 of Protocol for Regulatory Determination 3 April 2014

7 of 84 occurring at “levels and frequencies of public hea lth concern” with improved but varying analytical method/detection limits

• CA has large data set, most sensitive analytical method of state data and has 4% of systems with detections >HRL. Although improved, detection limit for CA is higher than HRL and CA likely has more occurrence >HRL that is undetected.

• Release to the environment has increased from 2004 to 2006 although production has decreased from 1998 to 2002.

• Being considered as part of the carcinogenic Volatile Organic Compounds ( CVOC s) group regulatory effort.

• On UCMR 3 3. 1,3

- Dinitrobenzene

• CASRN = 99650

• Substance Key = 4045

• A nitrated aromatic compound

• Used as an industrial chemical

Production / Release Data

TRI

- Release 20 10

• Surface water = 0 lbs/yr ( 0 states )

• Total = 10,595 lbs/yr ( 1 state )

TRI

- Release 200 8

• Surface water = 2 lbs/yr ( 1 state )

• Total = 19,858 lbs/yr ( 1 state )

TRI

- Release 2006

• Surface water = 0 lbs/yr (0 states) Critical Health Endpoint

• Increased spleen weight ( Cody et al., 1981 )

• NOAEL = 0.4 mg/kg

- day

• UF = 3,000

• RfD = 0.0001 mg/kg

- day

• Non

- cancer HRL = 0.7 μg/L

Health Assessment Status

• Update not needed (no additional information)

o IRIS (1988); completed a comprehensive review of toxicological studies; a change to the RfD was not warranted (May 2005)

o Not classifiable as to human carcinogenicity, group D (1986 cancer guidelines)

o The ATSDR (1995) assessment is consistent

Sensitive Populations/Lifestages

• Individuals with genetic predisposition to methemoglobinemia and/or iron Analyzed using HRL of 0.7 μg/L

National Drinking Water Data

UCMR 2 Finished Water Assessment Monitoring (2008

- 2010)

• MRL = 0.8 μg/L

• Not detected in 32,017 samples from 4,137 PWSs

Supplementary Ambient/Source Water Data

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 2 states

• No GW detects in 48 samples from 17 sites

• No SW detects >1⁄2HRL or >HRL

• % SW samples w/ detects = 100% (95 of 95)

• % SW sites w/ detects = 100% (53 of 53)

• Median detect = 0.04 μg/L

• 90%ile detect = 0.31 μg/L

• Max detect = 0.33 μg/L
1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

Occurrence summary and/or additional information: Proceeds to phase 3

Rationale: The contaminant has no or low potential of public health concern and does not have critical health or occurrence data gaps

Health: Available health assessment; an update will not be needed

Occurrence: No detections in national finished water dataPhase 2 of Protocol for Regulatory Determination 3 April 2014

8 of 84 • Total = 17,745 lbs/yr (1 state)

TRI

- Release 2004

• Surface water = 2 lbs/yr (1 state)

• Total = 528,962 lbs/yr (1 state)

_______________________ Fate / Transport

• Expected to be moderately to highly mobile in water, based on physical and chemical properties

• Moderately persistent in the environment (biodegrades slowly with acclimation ) ( CCL CIS ) disorders , neonates, and those co

exposed to other hemolytic agents

• Males having sperm production complications • No detections in recent national data (UCMR 2); minimal uncertainty because detection limit slightly higher than HRL

• Total releases and releases to surface water have decreased from

2004 to 2006

4. 1,4

- Dioxane

• CASRN = 123911

• Substance Key = 5539

• A cyclic aliphatic ether

• Commonly used as a solvent or solvent stabilizer in the manufacture and processing of paper, cotton, textile products, automotive coolant, cosmetics, and shampoos

• A disinfect byproduct

Production / Release Data

TRI

- Release 20 10

• Surface water = 23,007 Critical Health Endpoint

• Liver adenomas and carcinomas (Kano et al., 2009)

• CSF = 0.1 0 (mg/kg

- day) -1

• Cancer HRL = 0.4 μg/L

Non

- Cancer Health Effect

• Liver and kidney toxicity (Kociba et al., 1974)

• NOAEL = 9.6 mg/kg

- day

• UF = 3 00

• Chronic RfD = 0. 03 mg/kg

- day

• Non

- cancer HRL = 210 μg/L

Health Assessment Status

• Updated since CCL3

o IRIS (2010 ) Analyzed using HRL of 0.4 μg/L

Non -N ational Drinking Water Data

State Drinking Water Data (2001

- 2007)

• % systems w/ detects =

o CA: 11.01% (24 of 218)

• % systems w/ detects >1⁄2HRL =

o CA: 11.01% (24 of 218)

• % systems w/ detects >HRL =

o CA: 10.55% (23 of 218)

Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (2007)

• Detected in 1 CWS; max detect = 3.0 μg/L, >HRL Does not proceed to phase 3

Rationale: The contaminant has occurrence data gaps.

Health: Available health assessment

Occurrence: Does not have national finished water data or sufficient non

- national finished water dataPhase 2 of Protocol for Regulatory Determination 3 April 2014

9 of 84 lbs/yr ( 7 states )

• Total = 629,754 lbs/yr ( 16 states)

TRI

- Release 200 8

• Surface water = 41,014 lbs/yr (7 states )

• Total = 203,798 lbs/yr ( 20 states)

TRI

- Release 2006

• Surface water = 49,035lbs/yr (8 states)

• Total = 316,133 lbs/yr (19 states)

TRI

- Release 2004

• Surface water = 89,521 lbs/yr (7 states)

• Total = 821,067 lbs/yr (22 states)

CUSIUR Production Data

• >1M

- 10M lbs/yr (1998, 2002)

• 1 M – < 10 M lbs/yr (2006)

Fate / Transport

• Expected to be moderately to highly mobile in water, based on physical and chemical properties

• Moderately persistent in the environment (biodegrades slowly ) ( CCL CIS ) •

Sensitive Populations/Lifestages

• Individuals with compromised liver and kidney function

• Children CWSS (2 006)

• % samples w/ detects = 68% (17 of 25); max detect = 2.2 μg/L,

>HRL

EWG (2004

- 2009)

• At least 14 PWSs from 3 states w/ detects >HRL

Occurrence summary and/or other information:

• CA has detections >HRL, but it is a limited data set with ~200

systems

• On UCMR 3Phase 2 of Protocol for Regulatory Determination 3 April 2014

10 of 84 5. Acephate

• CASRN = 30560191

• Substance Key = 31325

• Organic phosphoramide pesticide

• U sed as an insecticide

Production / Release Data

OPP Estimated Environmental Concentrations

• Surface water chronic = 7.2 μg/L

• Ground water chronic = 0.02 μg/L

TRI

- Release 20 10

• Surface water = 0 lbs/yr ( 0 states )

• Total = 5,816 lbs/yr ( 2 states)

TRI

- Release 200 8

• Surface water = 0 lbs/yr ( 0 states )

• Total = 1,919 lbs/yr ( 3 states)

TRI

- Release 2006

• Surface water = 250 lbs/yr (1 state)

• Total = 25,608 lbs/yr ( 5 states) Critical Health Endpoint

• Brain Cholinesterase inhibition ( Chevron Chemical Company, 1982 )

• NOAEL = 0.12 mg/kg

- day

• UF = 100

• RfD = 0

. 0012 mg/kg

- day

• Non

- cancer HRL = 8.4 μg/L

Health Assessment Status

• Possible human carcinogen, group C ( 1986 cancer guidelines )

• OPP RED (2006)

Sensitive Populations/Lifestages

• None identified Analyzed using HRL of 8.4 μg/L

Non -N ational Drinking Water Data

State Drinking Water Data (199 8- 200 4)

• Max detect = 6 μg/L , >1⁄2 HRL

• % systems w/ detects =
o CA: 50.0 % ( 2 of 4) Does not proceed to phase 3

Rationale: The contaminant has occurrence data gaps.

Health: Available health assessment

Occurrence: Does not have national finished water data or sufficient non

- national finished water dataPhase 2 of Protocol for Regulatory Determination 3 April 2014

11 of 84 TRI

- Release 2004

• Surface water = 0 lbs/yr ( 0 states)

• Total = 20,789 lbs/yr ( 5 states)

NCFAP Total Pesticide Application 1997

• 2.5M lbs/yr (35 states)

Pesticide Industry Sales and Usage Report

• 1999: 2M

- 3M lbs

• 2001: 2 M- 3M lbs

• 2005: 4M

- 6M lbs

• 2007: 4M

- 6M lbs

RED 2006

• 4M

- 5M lbs of acephate active ingredient used annually

Fate / Transport

• Expected to be highly mobile in soils (HSDB)

• Particulate acephate is removed by atmospheric deposition (HSDB)



### • Not expected to volatilize from wet or dry soils (HSDB) 6. Acetochlor

• CASRN = 34256821

• Substance Key = 32393

• An acetanilide pesticide Critical Health Endpoint

• Lung tumors (Brunsman, 2004 )

• CSF = 0.0327 (mg/kg

- day) -1

• Cancer HRL = 1 μg/ L Analyzed using HRL of 1 μg/L

National Drinking Water Data Does not proceed to phase 3

Rationale: While acetochlor likely has no or low potential for public healthPhase 2 of Protocol for Regulatory Determination 3 April 2014

12 of 84 • Used as an herbicide for pre- emergence control of weeds

• Registered for use on field corn and popcorn. First registered in 1994

• Corn fields treated with acetochlor may later be rotated to grain sorghum (milo), soybeans, wheat, and tobacco, according to the currently registered use pattern

Production / Release Data

NCFAP Total Pesticide Application 1997

• 32,591,175 lbs/yr (35 states)

Pesticide Industry Sales and Usage Report

• 1997: 31M

- 36M lbs

• 1999: 30M

- 35M lbs

• 2001: 30M

- 35M lbs

• 2005: 26M

- 31M lbs

• 2007: 28M – 33M lbs

Fate / Transport

• Expected to be moderately to highly mobile in soils (HSDB)

• Degrades faster in warmer and moister soils, primarily Non

- Cancer Health Effect

• Histopathology (testes, kidney, and liver), increased alanine aminotransferase (ICI, Inc., 1988)

• NOAEL = 2 mg/kg

- day

• UF = 100

• RfD = 0.02 mg/kg

- day

• Non

- cancer HRL = 140 μg/L

Health Assessment Status

• Updated since CCL3

o OPP TRED (2006)

- cancer

• IRIS (199 2) – Non

- cancer

Sensitive Populations/Lifestages

• None identified UCMR 2 Finished Water Screening Survey (2008

- 2010)

• MRL = 2 μg/L

• Not detected in 11,138 samples from 1,198 PWSs

UCMR 1 Finished Water Assessment Monitoring (2001

- 2003)

• MRL = 2 μg/L

• Not detected in 33,778 samples from 3,869 PWSs

Non -N ational Drinking Water Data

State Drinking Water Data (1999

- 2007)

• All detects >1⁄2HRL and >HRL

• % systems w/ detects >HRL =

o IL: 0.11% (1 of 897)

o CA: Not detected from 279 systems

o OH: Not detected from 26 systems

Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (2006

- 2007)

• Not detected in 3 CWSs in NY

EWG (2004

- 2009)

• 2 PWSs from 2 states w/ detects >HRL

PDP Raw and Finished Water (2001

- 200 9)

• Max detect in finished water = 0.357 μg/L, < 1⁄2HRL

• Max detect in raw water = 0.669 μg/L, >1⁄2HRL

• % samples w/ detects = 4

. 25 % ( 224 of 5,272 ); no detects >HRL

PMP Raw Water (1999)

• No max detects >HRL in 323 samples

PMP Finished Water (1999) concern based on national finished water data, it might be considered as a group along with other chloroacetanilides and/or their degradates in the future. And at this time, the Agency does not have a health assessment for the degradates (i.e., a health data gap).

Health: Health assessments for the degradates will not be completed by Fall 2011

Occurrence: No detections for Acetochlor (parent) in national finished water dataPhase 2 of Protocol for Regulatory Determination 3 April 2014

13 of 84 through microbial activity • No max detects >HRL in 228 samples

Wisconsin GW Study (1999

- 2000)

• % monitoring wells w/ detects = 3.7% (1 of 27); avg. detect = 1.2 μg/L, >HRL

Iowa Well Water Study (2006

- 2008)

• % samples w/ detects = 1% (1 of 469); no detects >1⁄2HRL or >HRL

Supplemental Ambient/Source Water Data

NAWQA Ambient Water (1992

- 2001)

• MRLs variable (0.001 – 0.004 μg/L)

• No GW detects >1⁄2HRL or >HRL

• % GW samples w/ detects = 0.31% (14 of 4,556)

• % SW samples w/ detects = 15.85% (1,950 of 12,306)

• % SW samples w/ detects >1⁄2HRL = 1. 9 9% ( 245 of 12,306)

• % SW samples w/ detects >HRL = 1. 40 % (1 72 of 12,306)

• % GW sites w/ detects = 0.35% (14 of 4,023)

• % SW sites w/ detects = 17.53% (264 of 1,506)

• % SW sites w/ detects >1⁄2HRL = 5.05 % (7 6 of 1,506)

• % SW sites w/ detects >HRL = 4. 25 % (6 4 of 1,506)

• Median detect = 0.032 μg/L

• 99%ile detect = 8.49 μg/L

• Max detect = 30.4 μg/L

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 1 7 states

• % GW samples w/ detects = 0.93 % ( 18 of 1, 927 )

• % GW samples w/ detects >1⁄2HRL = 0.36 % ( 7 of 1,927 )

• % GW samples w/ detects >HRL = 0. 26 % ( 5 of 1,927 )

• % SW samples w/ detects = 20.20 % ( 5,740 of 28,411 )

• % SW samples w/ detects >1⁄2HRL = 4.78 % ( 1,357 of 28,411 )

• % SW samples w/ detects > HRL = 2.62 % ( 744 of 28,411 )Phase 2 of Protocol for Regulatory Determination 3 April 2014

14 of 84 • % GW sites w/ detects = 2.17 % ( 9 of 415 )

• % GW sites w/ detects >1⁄2HRL = 0.24 % (1 of 415 )

• % GW sites w/ detects >HRL = 0.2 4 % (1 of 415 )

• % SW sites w/ detects = 52.49 % ( 833 of 1, 587 )

• % SW sites w/ detects >1⁄2HRL = 22.94 % ( 364 of 1,587 )

• % SW sites w/ detects >HRL = 15.88 % ( 252 of 1,587 )

• Median detect = 0. 18 μg/L

• 90%ile detect = 1.4 μg/L

• Max detect = 117.80 μg/L
1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Pre sent”)

NAWQA Domestic Well Water Quality (1991

- 2004):

• % samples w/ detects = 0.1% (2 of 2,046); no detects >1⁄2HRL or >HRL

NAWQA Quality of Public Supply Wells (1993

- 2007; Toccalino et al.)

• MRL = 0.002 - 0.003 μg/L

• No detects >1⁄2HRL or >HRL

• % samples w/ detects = 0.25% (2 of 800)

NAWQA National Synthesis (1992

- 2001)

• MRL = 0.001 - 0.003 μg/L

• GW: no max detects >1⁄2HRL or >HRL

• SW: max detect from mixed land use sites (1.66 μg/L) and agricultural sites (10.6 μg/L) >HRL

USGS CWSs Drawing from Streams and Groundwater (2002

- 2005)

• Detects >HRL in Phase 1

o Phase 1 % GW detects = 0.5% (1 of 221); max detect = 0.037

μg/L

o Phase 1 % SW detects = 12.3% (18 of 146); max detect = 4.32

μg/L, >HRL

o Phase 2 % GW detects = 0.00% (0 of 51)

o Phase 2 % SW raw detects = 16.0% (14 of 90)

o Phase 2 % SW finished detects = 11.0% (10 of 87)Phase 2 of Protocol for Regulatory Determination 3 April 2014

15 of 84 Acetochlor Registration Partnership (1995

- 2001)

• % wells w/ detects in GW study = 0.08% (14 of 175); max detect = 4.35 μg/L, >HRL

• Max detect of 175 sites in SW study = 18.2 μg/L, >HRL

• Max annualized mean conc. of 175 sites in SW study = 1.43 μg/L, >HRL

CDC Fourth National Report (2003

- 2004)

• 95%iles <LOD in 2,501 urine samples

Occurrence summary and/or other information:

• No detections in recent national data (UCMR 2); Acetochlor (parent) is potentially not occurring at levels of public health concern

• Frequent detections in ambient water with some detections >HRL

• Acetochlor and other chloroacetanilides may be considered as a group

7. Acetochlor ethanesulfonic acid (ESA)

• CASRN = 187022113

• Substance Key = 79191

• An acetanilide pesticide degradate

• See also parent compound

Production / Release Data No data for production and release

Fate / Transport

• In water, acetochlor ESA mobility > acetochlor OA mobility > acetochlor mobility Critical Health Endpoint

• P arent (Acetochlor) i s surrogate

• Lung tumors (Brunsman, 2004 )

• CSF = 0.0327 (mg/kg

- day) -1

• Cancer HRL = 1 μg/L

Non

- Cancer Health Effect

• Supplemental OPP data

• Decreased body weights, decreased body weight gains, and decreased food utilization (Lees 2000)

• NOAEL = 230 mg/kg

- day

• UF = 1,000

• RfD = 0.23 mg/kg

- day

• Non

- cancer HRL = 161 μg/L

Health Assessment Status

• Parent compound [OPP TRED 2006] Analyzed using HRL of 1 μg/L

National Drinking Water Data

UCMR 2 Finished Water Screening Survey (2008

- 2010)

• MRL = 1 μg/L

• All detects >HRL

• % samples w/ detects >HRL = 0.02% (2 of 11,100)

• % PWSs w/ detects >HRL = 0.17% (2 of 1,198)

• Median detect = 1.15 μg/L

• 99%ile detect = 1.2 μg/L

• Max detect = 1.2 μg/L

Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (2007)

• Not detected in 1 CWS in NY Does not proceed to phase 3

Rationale: While acetochlor ESA has no or low detections based on national finished water data, there is no health assessment for the ESA degradate and it difficult to assess whether it is occurring at levels of concern. Also, acetochlor ESA might be considered as a group along with other chloroacetanilides and/or their degradates in the future.

Health: Health assessment for Acetochlor ESA (degradate) will not be completed by Fall 2011Phase 2 of Protocol for Regulatory Determination 3 April 2014

16 of 84 • Subject to microbial degradation, though more stable than parent compound Sensitive Populations/Lifestages

• None identified PDP Raw and Finished Water (2001

- 2009 )

• Max detect in finished water = 1.2 μg/L, >HRL

• Max detect in raw water = 1.9 μg/L, >HRL



### • % samples w/ detects = 28.32% (1,260 of 4,449)

Wisconsin GW Study (1999

- 2000)

• Avg. detect in 27 monitoring wells = 2.9 μg/L, >HRL

• Avg. detect in 22 private drinking water wells = 1.8 μg/L, >HRL

Iowa Well Water Study (2006

- 2008)

• % samples w/ detects = 11% (53 of 472); max detect = 1.20 μg/L, >HRL

Supplemental Ambient/Source Water Data

USGS CWSs Drawing from Streams and Groundwater (2002

- 2005)

• Detects >HRL in Phase 1

o Phase 1 % GW detects = 1.4% (1 of 73); max detect = 0.07 μg/L,

no detects > 1⁄2HRL or >HRL

o Phase 1 % SW detects = 41.0% (16 of 39); max detect = 1.42

μg/L, >HRL

o Phase 2 % GW raw detects = 19.0% (6 of 32); max detect = 0.77

μg/L, >1⁄2HRL

o Phase 2 % GW finished detects = 19.0% (6 of 32); max detect = 0.8

μg/L, >1⁄2HRL

o Phase 2 % SW raw detects = 25.0% (12 of 49); max detect = 0.40

μg/L, no detects > 1⁄2HRL or >HRL

o Phase 2 % SW finished detects = 27.0% (13 of 48); max detect =

0.31 μg/L, no detects > 1⁄2HRL or >HRL

Acetochlor Registration Partnership (1999

- 2001)

• % wells w/ detects in GW study = 46.29% (81 of 175); max detect = 20 μg/L, >HRL

• Max detect of 175 sites in SW study = 3.32 μg/L, >HRL

• Max annualized mean conc. of 175 sites in SW study = 1.01 μg/L, >HRL Occurrence: Two detections for Acetochlor ESA (degradate) in national finished water dataPhase 2 of Protocol for Regulatory Determination 3 April 2014

17 of 84 Occurrence summary and/or other information:

• Two detections in national data (UCMR 2); All detections for Acetochlor ESA in UCMR 2 are ≥ to parent (Acetochlor) HRL due to detection limit

• S upplemental drinking water and ambient water data demonstrate some detections of Acetochlor ESA > parent (Acetochlor) HRL 8. Acetochlor oxanilic acid (OA)

• CASRN = 194992444

• Substance Key = 79193

• An acetanilide pesticide degradate

• See also parent compound

Production / Release Data No data for production and release

Fate / Transport

• In water, acetochlor ESA mobility > acetochlor OA mobility > acetochlor mobility

• Subject to microbial deg radation, though more stable than parent compound Critical Health Endpoint

• P arent (Acetochlor) i s surrogate

• Lung tumors (Brunsman, 2004 )

• CSF = 0.0327 (mg/kg

- day) -1

• Cancer HRL = 1 μg/L

Non

- Cancer Health Effect

• Supplemental OPP data

• Decreased body weights, decreased body weight gains, and decreased food utilization (Williams 2000)

• NOAEL = 230 mg/kg

- day

• UF = 1,000

• RfD = 0.23 mg/kg

- day

• Non

- cancer HRL = 161 μg/L

Health Assessment Status

• Parent compound [OPP TRED 2006]

Sensitive Populations/Lifestages

• None identified Analyzed using HRL of 1 μg/L

National Drinking Water Data

UCMR 2 Finished Water Screening Survey (2008

- 2010)

• MRL = 2 μg/L

• Not detected in 11,100 samples from 1,198 PWSs

Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (2007)

• Not detected in 1 CWS in NY

PDP Raw and Finished Water (2001

- 2009 )

• Max detect in finished water = 1.3 μg/L, >HRL

• Max detect in raw water = 1.9 μg/L, >HRL

• % samples w/ detects = 24.09% (1,199 of 4,976)

Wisconsin GW Study (1999

- 2000)

• Avg. detect in 27 monitoring wells = 0.94 μg/L, >1⁄2HRL

• Avg. detect in 22 drinking water wells = 1.1 μg/L, >HRL

Iowa Well Water Study (2006

- 2008)

• % samples w/ detects = 1% (6 of 472); max detect = 0.150 μg/L, no detects > 1⁄2HRL or >HRL

Supplemental Ambient/Source Water Data Does not proceed to phase 3

Rationale: While acetochlor OA has no or low detections based on national finished water data, there is no health assessment for the OA degrad ate and it difficult to assess whether it is occurring at levels of concern. Also, acetochlor OA might be considered as a group along with other chloroacetanilides and/or their degradates in the future.

Health: Health assessment for Acetochlor OA (degr adate) will not be completed by Fall 2011

Occurrence: No detections for Acetochlor OA (degradate) in national finished water dataPhase 2 of Protocol for Regulatory Determination 3 April 2014

18 of 84 USGS CWSs Drawing from Streams and Groundwater (2002

- 2005)

• Detects >HRL in Phase 1

o Phase 1 % GW detects = 1.4% (1 of 73); max detect = 0.12 μg/L

o Phase 1 % SW detects = 38.5% (15 of 39); max detect = 1.74

μg/L, >HRL

o Phase 2 % GW raw detects = 9.4% (3 of 32); max detect = 0.41

μg/L

o Phase 2 % GW finished detects = 19% (6 of 32); max detect = 0.53

μg/L

o Phase 2 % SW raw detects = 32% (16 of 49); max detect = 0.65

μg/L

o Phase 2 % SW finished detects = 25% (12 of 48); max detect = 0.40

μg/L

Acetochlor Registration Partnership (1999

- 2001)

• % wells w/ detects in GW study = 14.86% (26 of 175); max detect =

19.1 μg/L, >HRL

• Max detect of 175 sites in SW study = 6.34 μg/L, >HRL

• Max annualized mean conc. of 175 sites in SW study = 1.69 μg/L, >HRL

Occurrence summary and/or other information:

• No detections in national data (UCMR 2); All detections in UCMR 2

are > parent (Acetochlor) HRL due to detection limit

• Supplemental drinking water and ambient water data demonstrate

some detections for Acetochlor OA > parent (Acetochlor) HRL 9. Alachlor ethanesulfonic acid (ESA)

• CASRN = 142363539

• Substance Key = 71246

• An acetanilide pesticide degradate

Production / Release Data

TRI

- Release 20 10 (alachlor)

• Surface water = 9 lbs/yr ( 1 Critical Health Endpoint

• Using parent (Alachlor) as a surrogate

• CSF = 0.08 (mg/kg

- day) -1

• Cancer HRL = 0.4 μg/L

Non

- Cancer Health Effect

• Supplemental OPP data

• Decreased body weight

• Supplemental NOEL = 157 mg/kg

day



### • UF = 1,000 Analyzed using HRL of 0.4 μg/L

National Drinking Water Data

UCMR 2 Finished Water Screening Survey (2008

- 2010)

• MRL = 1 μg/L

• All detects >HRL

• % samples w/ detects >HRL= 0.05% (5 of 11,099)

• % PWSs w/ detects >HRL= 0.25% (3 of 1,198)

• Median detect = 1.20 μg/L

• 99%ile detect = 1.30 μg/L Does not proceed to phase 3

Rationale: While alachlor ESA has no or low detections based on national finished water data, there is no health assessment for the ESA degradate and it difficult to assess whether it is occurring at levels of concern. Also, alachlor ESA might be considered as a group along with other chloroacetanilides and/or their degradates in the future.Phase 2 of Protocol for Regulatory Determination 3 April 2014

19 of 84 state )

• Total = 182 lbs/yr ( 2 states)

TRI

- Release 200 8 (alachlor)

• Surface water = 9 lbs/yr ( 1 state )

• Total = 368 lbs/yr ( 2 states)

TRI

- Release 2006 (alachlor)

• Surface water = 12 lbs/yr (1 state)

• Total = 274 lbs/yr (1 state)

TRI

- Release 2004 (alachlor)

• Surface water = 9 lbs/yr (1 state)

• Total = 1,522 lbs/yr (3 states)

NCFAP Total Pesticide Application 1997

• 15M lbs/yr (47 states) (alachlor)

Pesticide Industry Sales and Usage Report

• 1987: 55M

- 60M lbs (alachlor)

• 1997: 13M

- 16M lbs (alachlor)

• 1999: 7M

- 10M lbs (alachlor)

• 2001: 6M

- 9M lbs (alachlor)

RED 1998

• 29.3M

- 44.6M lbs of alachlor active ingredient were used annually 1993

- 1995 

### • RfD = 0.16 mg/kg

- day

• Non

- cancer HRL = 1,100 μg/L

Health Assessment Status

• Parent compound [OPP RED 1998]

Sensitive Populations/Lifestages

• None identified

Alachlor, the parent compound, is already regulated with an MCL of 2 μg/L • Max detect = 1.30 μg/L

Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (2007)

• Detected in 1 CWS; max detect = 0.58 μg/L, >HRL

CWSS (2006)

• Detected in 1 sample; max detect = 0.35 μg/L, >1⁄2HRL

PDP Raw and Finished Water (2001

- 200 9)

• Max detect in finished water = 1.443 μg/L, >HRL

• Max detect in raw water = 1.037 μg/L, >HRL

• % samples w/ detects = 3 6. 81 % ( 1,708 of 4,640 )

6- year Review – ICR [Alachlor parent] (1998

- 2005)

• % systems w/ detects of parent compound = 0.33% (of approx. 37,000); max detect = 14 μg/L, >HRL

National Pesticide Survey (1988

- 1990)

• MRL = 0.50 μg/L

• Parent compound not detected in samples from 566 CWS wells and 783 rural domestic wells

Iowa Well Water Study (2006

- 2008)

• % samples w/ detects = 27% (126 of 472); 75%ile and maximum detect >HRL

Wisconsin GW Study (1993)

• % samples w/ detects = 70.0% (205 of 293); max detect = 26.7 μg/L, >HRL

Supplemental Ambient/Source Water Data

NAWQA Ambient Water [Alachlor parent] (1992

- 2001) Health: Health assessment for Alachlor ESA (degradate) will not be completed by Fall 2011

Occurrence: No detections for Alachlor ESA (degradate) in national finished water dataPhase 2 of Protocol for Regulatory Determination 3 April 2014

20 of 84 Fate / Transport

• Very mobile in soils; ten times more soluble than alachlor in water.

• Subject to microbial degradation, though more stable than parent compound • MRLs variable (0.0012 – 0.003 μg/L)

• % sites w/ detects = 7.93% (568 of 7,166)

• Max detect = 38.2 μg/L, >HRL

USGS Study in 12 Midwestern states (1991

- 1994)

• % samples w/ detects = 46% (of 153 wells); max detect = 8.6 μg/L, >HRL

USGS CWSs Drawing from Streams and Groundwater (2002

- 2005)

• Detects >HRL

o Phase 1 % GW detects = 34.5% (20 of 58); max detect = 0.64

μg/L. >HRL

o Phase 1 % SW detects = 59.0% (23 of 39); max detect = 0.24

μg/L

o Phase 2 % GW raw detects = 77.0% (13 of 17); max detect = 0.68

μg/L, >HRL

o Phase 2 % GW finished detects = 77.0% (13 of 17) ; max detect =

0.53 μg/L, >HRL

o Phase 2 % SW raw detects = 61% (30 of 49) ; max detect = 0.27

μg/L

o Phase 2 % SW finished detects = 59% (28 of 48) ; max detect = 0.37

μg/L

Acetochlor Registration Partnership (1999

- 2001)

• % wells w/ detects in GW study = 43.43% (76 of 175)

• % samples w/ detects in SW study = 14%

Iowa Study (1995)

• % samples w/ detects = 65.0% (69 of 106); max detect = 14.8 μg/L, >HRL

Occurrence in the Lower Mississippi River (1991

- 1997)

• % samples w/ detects = 96% (154 of 160); median detect = 0.6 μg/L, >HRL

Occurrence in Rivers & Reservoirs of Midwestern U.S. ( 1990

- 1993)

• Median detect in 76 reservoirs = 0.48 μg/L, >HRL

• Range of detects in Mississippi River mouth/headwaters = 0.2

– 1.5Phase 2 of Protocol for Regulatory Determination 3 April 2014

21 of 84 μg/L

Alachlor REDs - EPA OPP (1982

- 1996)

• 15 studies; all studies w/ detects >HRL

• Range of detects = 0.23 – 135 μg/L

• Range of max detects = 5.6 – 135 μg/L

CDC Fourth National Report (2003

- 2004)

• 95%iles <LOD for alachlor mercapturate in 1,942 urine samples

Occurrence summary and/or other information:

• Five detections in national data (UCMR 2); All detections for Alachlor ESA in UCMR are >parent (Alachlor) HRL due to detection limit

• Supplemental drinking water and ambient water data demonstrate some detections of Alachlor ESA > parent HRL

10. Alachlor oxanilic acid (OA)

• CASRN = 171262172

• Substance Key = 79196

• An acetanilide pesticide degradate

Production / Release Data

TRI

- Release 20 10 (alachlor)

• Surface water = 9 lbs/yr ( 1 state )

• Total = 182 lbs/yr ( 2 states)

TRI

- Release 200 8 (alachlor)

• Surface water = 9 lbs/yr ( 1 state )

• Total = 368 lbs/yr ( 2 states)

TRI

- Release 2006 (alachlor) Critical Health Endpoint

• Using parent (Alachlor) as a surrogate

• CSF = 0.08 (mg/kg

- day) -1

• Cancer HRL = 0.4 μg/L

Non

- Cancer Health Effect

• Supplemental OPP data

• Decreased body weight

• Supplemental NOEL = 157 mg/kg

day

• UF = 1,000

• RfD = 0.16 mg/kg

- day

• Non

- cancer HRL = 1,100 μg/L

Health Assessment Status

• Parent compound [OPP RED 1998]

Sensitive Populations/Lifestages Analyzed using HRL of 0.4 μg/L

National Drinking Water Data

UCMR 2 Finished Water Screening Survey (2008

- 2010)

• MRL = 2 μg/L

• Not detected in 11,100 samples from 1,198 PWSs

Supplemental Drinking Water Data Recent CCRs from 26 CWSs that serve >1M (2007)

• Not detected in 1 CWS

CWSS (2006)

• Not detected in 94 CWS

PDP Raw and Finished Water (2001

- 200 9)

• Max detect in finished water = 0.4995 μg/L, >HRL

• Max detect in raw water = 0.102 μg/L, < 1⁄2HRL Does not proceed to phase 3

Rationale: While alachlor OA has no or low detections based on national finished water data, there is no health assessment for the OA degradate and it difficult to assess whether it is occurring at levels of concern. Also, alachlor OA might be considered as a group along with other chloroacetanilides and/or their degradates in the future.

Health: Health assessment for Alachlor OA (degradate) will not be completed by Fall 2011

Occurrence: No detections for Alachlor OAPhase 2 of Protocol for Regulatory Determination 3 April 2014

22 of 84 • Surface water = 12 lbs/yr (1 state)

• Total = 274 lbs/yr (1 state)

TRI

- Release 2004 (alachlor)

• Surface water = 9 lbs/yr (1 state)

• Total = 1,522 lbs/yr ( 3 states)

NCFAP Total Pesticide Application 1997

• 15M lbs/yr (47 states) (alachlor)

Pesticide Industry Sales and Usage Report

• 1987: 55M

- 60M lbs (alachlor)

• 1997: 13M

- 16M lbs (alachlor)

• 1999: 7M

- 10M lbs (alachlor)

• 2001: 6M

- 9M lbs (alachlor)

RED 1998

• 29.3M

- 44.6M lbs of alachlor active ingredient were used annually 1993

- 1995

Fate / Transport

• Expected to be less mobile than alachlor ESA

• Subject to microbial degradation, though more stable than parent compound • None identified

Alachlor, the parent compound, is already regulated with an MCL of 2 μg/L • % samples w/ detects = 21.44% (1,068 of 4,981)

6- year Review – ICR [Alachlor parent] (1998

- 2005)

• % systems w/ detects of parent compound = 0.33% (of approx. 37,000); max detect = 14 μg/L, >HRL

National Pesticide Survey (1988

- 1990)

• MRL = 0.50 μg/L

• Parent compound not detected in samples from 566 CWS wells and 783 rural domestic wells

Iowa Well Water Study (2006

- 2008)

• % samples w/ detects = 3% (14 of 472); 75%ile and max detects >HRL

Wisconsin GW Study (1993)

• % samples w/ parent compound detects = 4.0%; max detect = 6.91 μg/L, >HRL

Supplemental Ambient/Source Water Data

NAWQA Ambient Water [Alachlor parent] (1992

- 2001)

• MRLs variable (0.0012 – 0.003 μg/L)

• % sites w/ detects = 7.93% (568 of 7,166)

• Max detect = 38.2 μg/L, >HRL

USGS CWSs Drawing from Streams and Groundwater (2002

- 2005)

• Detects >HRL

o Phase 1 % GW detects = 5.5% (4 of 73); max detect = 1.23 μg/L,

>HRL

o Phase 1 % SW detects = 41.0% (16 of 39); max detect = 0.13

μg/L

o Phase 2 % GW raw detects = 25.0% (8 of 32); max detect = 0.84

μg/L, >HRL

o Phase 2 % GW finished detects = 28.0% (9 of 32); max detect =

0.75 μg/L, >HRL

o Phase 2 % SW raw detects = 50% (24 of 49); max detect = 0.26 (degradate) in national finished water dataPhase 2 of Protocol for Regulatory Determination 3 April 2014

23 of 84 μg/L

o Phase 2 % SW finished detects = 50% (24 of 48); max detect = 0.12

μg/L

Acetochlor Registration Partnership (1999

- 2001)

• % wells w/ detects in GW study = 9.14% (16 of 175)

• % samples w/ detects in SW study = 13%

Iowa Study (1995)

• % samples w/ parent compound detects = 7.5%; max detect = 0.6 μg/L, >HRL

Occurrence in Lower Mississippi River (1991

- 1997)

• % samples w/ parent compound detects = 28% (76 of 271); max detect > 0.5 μg/L, >HRL

Occurrence in Rivers & Reservoirs of Midwestern U.S. ( 1990

- 1993)

• Parent compound detected in 76 reservoirs; median detect <0.05

μg/L

Alachlor REDs - EPA OPP (1982

- 1996)

• 15 studies; all studies w/ detects >HRL

• Range of detects = 0.23 – 135 μg/L

• Range of max detects = 5.6 – 135 μg/L

CDC Fourth National Report (2003

- 2004)

• 95%iles <LOD for alachlor mercapturate in 1,942 urine samples

Occurrence summary and/or other information:

• No detections in national data (UCMR 2); All detections for Alachlor OA in UCMR are > parent (Alachlor) HRL due to detection limit

• Supplemental drinking water and ambient water data demonstrate some detections for Alachlor OA > parent (Alachlor) HRL 11. Chlorate

• CASRN = 14866683

• Substance Key = 24376

• Chlorate and its salts are Critical Health Effects

• Thyroid effects (NTP, 2005)

• BMDL = 28 mg/L as sodium chlorate, or 0.9 mg/kg

- day Analyzed using HRL of 210 μg/L

Non

- National Drinking Water Data Proceeds to phase 3

Rationale: The contaminant is of potential public health concern and does notPhase 2 of Protocol for Regulatory Determination 3 April 2014

24 of 84 powerful oxidizers

• Chlorate compounds are used as herbicides and disinfectants for drinking water treatment

Production / Release Data

NCFAP Total Pesticide Application 1997

• 7,262,000 lbs/yr (16 states) (sodium chlorate)

RED 2006

• 2.8M lbs of sodium chlorate active ingredient are used annually

Fate / Transport

• Sodium chlorate highly soluble; chlorate ion mobile in water (RED)

• Sodium chlorate persists in the soil for 0.5 to 5 years (HSDB) • UF = 30

• RfD = 0.03 mg/kg

- day

• Non

- cancer HRL = 210 μg/L

Health Assessment Status

• OPP RED (2006) used in draft OW

Health Advisory (2011) [finalized in 2013]

• Not likely to cause cancer at doses

below those that alter thyroid hormone homeostasis

Sensitive Populations/Lifestages

• Individuals with anemia and possibly those with a glucose -6- phosphate dehydrogenase deficiency DBP ICR (1997

- 1998)

• MRL unavailable (min detect = 20 μg/L)

• % samples w/ detects = 86.68% (1,490 of 1,719)

• % samples >1⁄2HRL = 51.08 % (878 of 1,719)

• % samples >HRL = 19.31% (332 of 1,719)

• % systems w/ detects = 97.56% (80 of 82)

• Median detect = 120 μg/L

• 99% detect = 990.55 μg/L

• Max detect = 2,234 μg/L

State Drinking Water Data (2001

- 2007)

• Detects >HRL

• % systems w/ detects =

o CA: 53.33% (24 of 45)

• % systems w/ detects >1⁄2HRL =

o CA: 37.78% (17 of 45)

• % systems w/ detects >HRL =

o CA: 22.22% (10 of 45)

Supplemental Drinking Water Data

CWSS (2006)

• % PWS w/ detects = 3.19% (3 of 94); max detect = 51 μg/L, no detects > 1⁄2HRL or >HRL

EWG (2004

- 2009)

• 10 PWSs in 6 states w/ detects >HRL

Occurrence summary and/or other information:

• DBP ICR is a non

- national monitoring program of large systems

• DBP ICR data is also supplemented by recent state data demonstrating detections >HRL

• Recent surveys (e.g. AWWA) indicate an increase in treatment practices that form chlorate (e.g. liquid hypochlorite, chlorine dioxide , ozone) under certain conditions have critical health or occurrence data gaps

Health: Available health assessment

Occurrence: Significant occurrence at levels of public health concern in non

- national finished water dataPhase 2 of Protocol for Regulatory Determination 3 April 2014

25 of 84 • On UCMR 3

12. Cobalt

• CASRN = 7440484

• Substance Key = 18870

• A naturally

- occurring element

• Commonly used in superalloys

Production / Release Data

TRI

- Release 20 10 (cobalt)

• Surface water = 2,957 lbs/yr ( 21 states )

• Total = 462,699 lbs/yr ( 37 states)

TRI

- Release 20 10 (cobalt compounds )

• Surface water = 98,836 lbs/yr (31 states )

• Total = 5,143,016 lbs/yr ( 45 states)

TRI

- Release 200 8 (cobalt)

• Surface water = 2,599 lbs/yr ( 18 states )

• Total = 754,613 lbs/yr ( 38 states)

TRI

- Release 200 8 (cobalt compounds )

• Surface water = 217,107 lbs/yr (30 states )

• Total = 6,288,524 lbs/yr ( 46 Critical Health Endpoint

• Blood effect - increased hemoglobin (human study) ( Davis and Fields, 1958 )

• LOAEL = 1 mg/kg

- day

• UF = 100

• ATSDR MRL = 0.01 mg/kg

- day

• Non

- cancer HRL = 70 μg/L

Health Assessment Status

• ATSDR (2004)

• On the 2012 IRIS Agenda

Sensitive Populations/Lifestages

• Individuals who exhibit a polymorphism in the HLA

- DP gene that makes them more susceptible to hard metal disease

• Individuals with ongoing respiratory illness (inhaled cobalt)

• Individuals with iron deficiency (oral exposure)

• Individuals with high alcohol consumption. Analyzed using HRL of 70 μg/L

National Drinking Water Data

NIRS Finished Water [GW only] (1984

- 1986)

• MRL = 6 μg/L

• No detects >1⁄2HRL or HRL

• % PWSs w/ detects = 0.30% (3 of 989)

• Median detect = 9.68 μg/L

• 99%ile detect = 10.63 μg/L

• Max detect = 10.65 μg/L

Non -N ational Drinking Water Data

State Drinking Water Data (1996

- 2007)

• No detects >1⁄2HRL or HRL

• % systems w/ detects =

o CA: 14.93% (10 of 67)

o IL: 4.55% (1 of 22)

o OH: 12.00% (3 of 25)

Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (2007)

• Cobalt

- 59 detected in 1 CWS; max detect = 9.4 μg/L, no detects

> 1⁄2HRL or >HRL

CWSS (20 06)

• Not detected in 1 CWS Does not proceed to phase 3

Rationale: The contaminant likely has no or low potential for public health concern, but has a health data gap

Health: Non

- EPA health a ssessment will not be updated by Fall 2011

Occurrence: No detections in national or non

national finished water data at levels of public health concern based on the draft HRL.Phase 2 of Protocol for Regulatory Determination 3 April 2014

26 of 84 states)

TRI

- Release 2006 (cobalt)

• Surface water = 760 lbs/yr (18 states)

• Total = 943,396 lbs/yr (37 states)

TRI

- Release 2006 (cobalt compounds)

• Surface water = 172,263 lbs/yr (29 states)

• Total = 7,518,390 lbs/yr (45 states)

TRI

- Release 200 4 (cobalt)

• Surface water = 1,277 lbs/yr (17 states)

• Total = 776,762 lbs/yr (3 8 states)

TRI

- Release 200 4 (cobalt

c ompounds)

• Surface water = 86,563 lbs/yr (30 states)

• Total = 6,918,970 lbs/yr (4 6 states)

Fate / Transport

• Speciation and environmental fate and transport in water are influenced by the presence of organic ligands, concentration of anions, pH, Supplemental Ambient/Source Water Data

NAWQA Ambient Water (1992

- 2001)

• MRLs variable (most within 1

- 2 μg/L)

• No SW detects >HRL

• % GW samples w/ detects = 26.38% (858 of 3,252)

• % GW samples w/ detects >1⁄2HRL = 0.43% (14 of 3,252)

• % GW samples w/ detects >HRL = 0.28% (9 of 3,252)

• % SW samples w/ detects = 13.12% (312 of 2,378)

• % SW samples w/ detects >1⁄2HRL = 0.08% (2 of 2,378)

• % GW sites w/ detects = 24.62% (715 of 2,904)

• % GW sites w/ detects >1⁄2HRL = 0.48% (14 of 2,904)

• % GW sites w/ detects >HRL = 0.31% (9 of 2,904)

• % SW sites w/ detects = 17.05% (67 of 393)

• % SW sites w/ detects >1⁄2HRL = 0.25% (1 of 393)

• Median detect = 0.22 μg/L

• 99%ile detect = 50.18 μg/L

• Max detect = 684.0 μg/L

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 45 states

• % GW samples w/ detects = 58.92 % ( 2,123 of 3,603 )

• % GW samples w/ detects >1⁄2HRL = 13.07 % ( 471 of 3,603 )

• % GW samples w/ detects >HRL = 2.58 % (9 3 of 3,603 )

• % SW samples w/ detects = 24. 62 % ( 22,697 of 92,176 )

• % SW samples w/ detects >1⁄2HRL = 2. 23 % ( 2,053 of 92,176 )

• % SW samples w/ detects >HRL = 1.50 % (1, 382 of 92,176 )

• % GW sites w/ detects = 62.01 % ( 581 of 937 )

• % GW sites w/ detects >1⁄2HRL = 14.73 % ( 138 of 937 )

• % GW sites w/ detects >HRL = 4.06 % (3 8 of 937 )

• % SW sites w/ detects = 43.08 % ( 7,261 of 16,855 )

• % SW sites w/ detects >1⁄2HRL = 6. 85 % ( 1,155 of 16,855 )

• % SW sites w/ detects >HRL = 4. 93 % ( 831 of 16,855 )

• Median detect = 1.8 μg/LPhase 2 of Protocol for Regulatory Determination 3 April 2014

27 of 84 and redox potential

• Ionic cobalt compounds will not volatilize from water (HSDB, 2009) • 90%ile detect = 39 μg/L

• Max detect = 245,800 μg/L
1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

NAWQA Quality of Public Supply Wells (1993

- 2007; Toccalino et al.)

• MRL = 0.01 μg/L – 1 μg/L

• No detects >1⁄2HRL or >HRL

• % samples w/ detects = 63.16% (396 of 627)

NAWQA Domestic Well Water Quality (1991

- 2004)

• MRL = 1 μg/L

• % samples w/ detects in aquifer studies = 34.2% (537 of 1,572); no detects >1⁄2HRL or >HRL

• % samples w/ detects in agricultural land

- use studies = 47.4% (37 of 78); no detects >1⁄2HRL or >HRL

U.S. Glacial Aquifer Study (1991

- 2003)

• Max detect (95 μg/L) in 847 GW samples >HRL

CDC Fourth National Report (2003

- 2004)

• 95%ile concentration = 1.16 μg/L in 2,558 urine samples

Occurrence summary and/or other information:

• No detections >1⁄2 HRL or >HRL in national data (NIRS), or in non

national drinking water data (CA)

• Some detections >HRL in ambient water data (STORET)

, (NAWQA)



### • On UCMR 3 13. Dimethoate

• CASRN = 60515

• Substance Key = 2413

• An organophosphate

• First registered in 1962

• Commonly used as an insecticide on field crops, (such as cotton), on orchard Critical Health Effect

• Cholinesterase inhibition ( American Cyanamid Company, 1986 )

• BMDL = 0.22 mg/kg

- day

• UF = 100

• RfD = 0.0022 mg/kg

- day

• Non

- cancer HRL = 15.4 μg/L Analyzed using HRL of 15.4 μg/L

National Drinking Water Data

UCMR 2 Finished Water Assessment Monitoring (2008

- 2010)

• MRL = 0.7 μg/L

• Not detected in 32,013 samples from 4,138 PWSs Proceeds to phase 3

Rationale: The contaminant has no or low potential for public health concern and does not have critical health or occurrence data gapsPhase 2 of Protocol for Regulatory Determination 3 April 2014

28 of 84 crops, on vegetable crops, in forestry, and for residential purposes

Production / Release Data

TRI

- Release 20 10

• Surface water = 5 lbs/yr ( 1 state )

• Total = 8,442 lbs/yr (1 state )

TRI

- Release 200 8

• Surface water = 5 lbs/yr ( 1 state )

• Total = 15,561 lbs/yr ( 2 states )

TRI

- Release 2006

• Surface water = 5 lbs/yr (1 state)

• Total = 7,148 lbs/yr (2 states)

TRI

- Release 2004

• Surface water = 2,615 lbs/yr (2 states)

• Total = 31,480 lbs/yr (4 states)

NCFAP Total Pesticide Application 1997

• 1,896,947 lbs/yr (43 states)

Pesticide Industry Sales and Usage Report

• 1999: 1M

- 2M lbs

• 2001: 1M

- 2M lbs Health Assessment Status

• OPP IRED (2007)

• Possible human carcinogen, group C (1986 cancer guidelines )

Sensitive Populations/Lifestages

• None identified Non -N ational Drinking Water Data

State Drinking Water Data (1995

- 2007)

• No detects >HRL

• % systems w/ detects =

o CA: 0.09% (2 of 2,153)

Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (2002

- 2007)

• Not detected in 1 CWS

PDP Raw and Finished Water (2001

- 200 9)

• Max detect in finished water = 0.068 μg/L, <1⁄2HRL

• Max detect in raw water = 0.0088 μg/L, <1⁄2HRL

• % samples w/ detects = 0.0 5 % ( 3 of 5,374 ); no detects >1⁄2HRL or >HRL

PMP Raw Water (1999)

• % samples w/ detects = 1.3% (4 of 317); no detects >1⁄2HRL or >HRL

PMP Finished Water (1999)

• Not detected in any samples

Supplemental Ambient/Source Water Data

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 7 states

• No detects >1⁄2HRL or >HRL

• % GW samples w/ detects = 1.04% (9 of 867)

• % SW samples w/ detects = 3.86% (171 of 4,432) Health: Available health assessment

Occurrence: No detections in national finished water dataPhase 2 of Protocol for Regulatory Determination 3 April 2014

29 of 84 • 2005: <1M lbs

• 2007: <1M lbs

IRED 2008

• ~1.8M lbs used annually

Fate / Transport

• Expected to be very mobile in water, based on physical and chemical properties

• Moderately persistent in the environment (biodegrades slowly with acclimation ) ( CCL CIS ) • % GW sites w/ detects = 1.53% (9 of 587)

• % SW sites w/ detects = 15.64% (33 of 211)

• Median detect = 0 μg/L

• 90%ile detect = 0.16 μg/L

• Max detect = 0.44 μg/L
1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

USGS CWSs Drawing from Streams and Groundwater (2002

- 2005)

• No detects >HRL

o Phase 1: Not detected in 221 GW samples

o Phase 1 % samples w/ SW detects = 1.46% (2 of 146); detects

<0.01 μg/L

o Phase 2: Not detected in 48 GW samples

CA DPR

• Max detect = 2.4 μg/L, no detects > 1⁄2HRL or >HRL

Occurrence summary and/or other information:

• No detections in recent national data (UCMR 2)

• Total releases and releases to surface water have decreased from

2004 to 2006 14. Disulfoton

• CASRN = 298044

• Substance Key = 6423

• An organophosphate pesticide

• Was used as an insecticide

• All remaining uses cancelled in 2009

Production / Release Data

OPP Estimated Environmental Concentrations

• Surface water chronic = 2.0

- Critical Health Endpoint

• Plasma, RBC, & brain cholinesterase inhibition

• NOAEL = 0.013 mg/kg

- day

• UF = 100

• RfD = 0.00013 mg/kg

- day

• Non

- cancer HRL = 0.91 μg/L

Health Assessment Status

• OPP RED (20 06)

• Evidence of noncarcinogenicity for humans, group E (1986 cancer guidelines) Analyzed using HRL of 0.91 μg/L

Non

- National Drinking Water Data

UCMR 1 Finished Water Screening Survey (2001

- 2003)

• MRL = 0.5 μg/L

• Not detected in 2,300 samples from 295 PWSs

State Drinking Water Data (1995

- 2007)

• Not detected from systems in 2 states (CA and IL)

Supplemental Drinking Water Data Does not proceed to phase 3

Rationale: The contaminant likely has no or low potential for public health concern, but has an occurrence data gap.

Health: Available health assessment

Occurrence: The contaminant does not have national finished water data. While there are non

- national finished water data showing no detections, there arePhase 2 of Protocol for Regulatory Determination 3 April 2014

30 of 84 16.7 μg/L

• Ground water = 0.02 μg/L

NCFAP Total Pesticide Application 1997

• 1,196,066 lbs/yr (32 states)

RED 2007

• ~1.2M lbs active ingredient used annually in the 1990s

Fate / Transport

• Expected to be of low to moderate mobility in water, based on physical and chemical properties

• Moderately persistent in the environment (biodegrades slowly ) ( CCL CIS ) Sensitive Populations/Lifestages

• None identified in humans Recent CCRs from 26 CWSs that serve >1M (2002

- 2003)

• Not detected in 1 CWS

EWG (2004

- 2009)

• Not detected in samples from 332 PWSs

PDP Raw and Finished Water (2001

- 2009 )

• Not detected in 5,871 samples

PMP Raw & Finished Water (1999)

• Not detected in any raw or finished samples

Supplemental Ambient/Source Water Data

NAWQA Ambient Water (1992

- 2001)

• MRLs variable (most within 0.017

- 0.021 μg/L)

• No GW detects >1⁄2HRL or >HRL

• % GW samples w/ detects = 0.02% (1 of 6,080)

• % SW samples w/ detects = 0.17% (25 of 14,879)

• % SW samples w/ detects >1⁄2HRL = 0.02% (3 of 14,879)

• % SW samples w/ detects >HRL = 0.01% (2 of 14,879)

• % GW sites w/ detects = 0.02% (1 of 5,211)

• % SW sites w/ detects = 0.84% (16 of 1,907)

• % SW sites w/ detects >1⁄2HRL = 0.16% (3 of 1,907)

• % SW sites w/ detects >HRL = 0.10% (2 of 1,907)

• Median detect = 0.02 μg/L

• 99%ile detect = 3.81 μg/L

• Max detect = 3.81 μg/L

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 17 states

• No GW detects >1⁄2HRL or >HRL

• No SW detects >HRL

• % G W samples w/ detects = 17 .46% (3 3 of 189 ) some detections of potential public health concern in ambient water data.Phase 2 of Protocol for Regulatory Determination 3 April 2014

31 of 84 • % SW samples w/ detects = 5.28 % ( 257 of 4,863 )

• % SW samples w/ detects >1⁄2HRL = 0.0 2 % (1 of 4,863 )

• % GW sites w/ detects = 22.86 % ( 32 of 140 )

• % SW sites w/ detects = 21.73 % ( 113 of 520 )

• % SW sites w/ detects >1⁄2HRL = 0. 19 % (1 of 520)

• Median detect = 0 μg/L

• 90%ile detect = 0. 133 μg/L

• Max detect = 0.56 μg/L
1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

NAWQA Domestic Well Water Quality (1991

- 2004)

• MRL = 0.011 μg/L – 0.017

• % sa mples w/ detects = 0.04% (1 of 2,539); no detects >1⁄2HRL or >HRL

NAWQA Quality of Public Supply Wells (1993

- 2007; Toccalino et al.)

• MRL = 0.01 μg/L – 0.02 μg/L

• Not detected in 647 samples

NAWQA National Synthesis (1992

- 2001)

• MRL = varies - maximum of 0.011 μg/L

• No detects in any GW samples

• SW samples: 2,013 samples from 83 agricultural sites; max detect = 3.340 μg/L, >HRL. 1,386 samples from 65 mixed land use sites; max detect = 0.826, >1⁄2HRL

Virginia Tech Monitoring

• Detects in 3 samples from 2 of 8 sites; detects >HRL

• Max detect = 6.11 μg/L, >HRL

Occurrence summary and/or other information:

• No detections in UCMR1 (SS), which is a statistically defined, national sample of 300 PWSs

• USGS ambient water study demonstrates some detections >HRL

• Users voluntarily cancelled all product registrations but existing stocks can be used until June 2011Phase 2 of Protocol for Regulatory Determination 3 April 2014

32 of 84 15. Diuron

• CASRN = 330541

• Substance Key = 6583

• A halogenated aromatic urea pesticide

• Used as an herbicide

• Approved for use on 33 crops, including citrus, berries, asparagus and pineapple, plus other uses including as a mildewcide and preservative in paints and stains and as an algaecide in commercial fish production, residential ponds, and aquariums

Production / Release Data

TRI

- Release 20 10

• Surface water = 5 lbs/yr ( 1 state )

• Total = 63,477 lbs/yr ( 6 states)

TRI

- Release 200 8

• Surface water = 5 lbs/yr ( 1 state )

• Total = 91,471 lbs/yr ( 7 states)

TRI

- Release 2006

• Surface water = 5 lbs/yr (1 state) Critical Health Endpoint

• Urinary bladder carcinomas

• CSF = 0.0191 (mg/kg

- day) -1

• Cancer HRL = 1.8 μg/L

Non

- Cancer Health Effects

• Hemolytic anemia (du Pont, 1964)

• LOAEL = 1.0 mg/kg

- day

• UF = 300

• RfD = 0.003 mg/kg

- day

• Non

- cancer HRL = 21 μg/L

Health Assessment Status

• OPP RED (2003)

Sensitive Populations/Lifestages

• None identified Analyzed using HRL of 1.8 μg/L

Non -N ational Drinking Water Data

UCMR 1 Finished Water Screening Survey (2001

- 2003)

• MRL = 1 μg/L

• All detects (single detect) >HRL

• % PWSs w/ detects >HRL = 0.34% (1 of 293)

• Median detect = 2.1 μg/L

• 99%ile detect = 2.1 μg/L

• Max detect = 2.1 μg/L

State Drinking Water Data (1995

- 2007)

• % systems w/ detects =

o CA: 1.82% (18 of 990)

o IL: Not detected from 1 system

• % systems w/ detects >1⁄2 HRL =

o CA: 1.72% (17 of 990)

• % systems w/ detects >HRL =

o CA: 1.52% (15 of 990)

Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (2006

- 2007)

• Not detected in 1 CWS

EWG (2004

- 2009)

• One PWS w/ detect >1⁄2HRL and >HRL = 4.9 μg/L

• One PWS w/ detect >1⁄2HRL = 1.5 μg/L

PDP Raw and Finished Water (2002

- 2009 )

• Max detect in finished water = 0.267 μg/L, <1⁄2 HRL Does not proceed to phase 3

Rationale: The contaminant likely has no or low potential for public health concern, but has an occurrence data gap.

Health: Available health assessment

Occurrence: The contaminant does not have national finished water data. While there are non

- national finished wate r showing no detections, there are some detections of potential public health concern in ambient water data.Phase 2 of Protocol for Regulatory Determination 3 April 2014

33 of 84 • Total = 1,054 lbs/yr (7 states)

TRI

- Release 2004

• Surface water = 10 lbs/yr (2 states)

• Total = 822 lbs/yr (6 states)

NCFAP Total Pesticide Application 1997

• 4,370,448 lbs/yr (39 states)

Pesticide Industry Sales and Usage Report

• 1999: 2M

- 4M lbs

• 2001: 3M

- 6M lbs

• 2003: 4M

- 6M lbs

• 2005: 4M

- 6M lbs

• 200 7 : 2M

- 4M lbs

RED 2003

• ~9M

- 10M lbs of active ingredient used annually

CUSIUR Production Data

• >1M

- 10M lbs/yr (1998)

Fate / Transport

• Expected to be moderately to highly mobile in water, based on physical and chemical properties

• Persistent in the environment (biodegrades sometimes ) ( CCL CIS ) • Max detect in raw water = 0.309 μg/L, <1⁄2 HRL

• % samples w/ detects = 9 .8 9 % ( 395 of 3, 995 ); no detects >1⁄2HRL or >HRL

PMP Raw & Finished Water (1999)

• No detect >1⁄2HRL or >HRL in 312 raw water samples and 224

finished water samples

National Pesticide Survey (1988

- 1990)

• MRL = 0.32 μg/L

• Not detected in 566 CWS wells and 783 rural domestic wells

Supplemental Ambient/Source Water Data

NAWQA Ambient Water (1992

- 2001)

• MRLs variable (most are 0.002 μg/L)

• % GW samples w/ detects = 3.33% (134 of 4,030)

• % GW samples w/ detects >1⁄2HRL = 0.15% (6 of 4,030)

• % GW samples w/ detects >HRL = 0.10% (4 of 4,030)

• % SW samples w/ detects = 16.35% (906 of 5,541)

• % SW samples w/ detects >1⁄2HRL = 1.79% (99 of 5,541)

• % SW samples w/ detects >HRL = 1.05% (58 of 5,541)

• % GW sites w/ detects = 3.36% (123 of 3,656)

• % GW sites w/ detects >1⁄2HRL = 0.16% (6 of 3,656)

• % GW sites w/ detects >HRL = 0.11% (4 of 3,656)

• % SW sites w/ detects = 21.88% (196 of 896)

• % SW sites w/ detects >1⁄2HRL = 3.24% (29 of 896)

• % SW sites w/ detects >HRL = 1.67% (15 of 896)

• Median detect = 0.09 μg/L

• 99%ile detect = 8.4 μg/L

• Max detect = 23.3 μg/L

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 9 statesPhase 2 of Protocol for Regulatory Determination 3 April 2014

34 of 84 • No SW detects >HRL

• % GW samples w/ detects = 4.63 % ( 37 of 7 99 )

• % GW samples w/ detects >1⁄2HRL = 0.2 5 % (2 of 799 )

• % GW samples w/ detects >HRL = 0.2 5 % (2 of 799 )

• % SW samples w/ detects = 77.11 % ( 155 of 201 )

• % SW samples w/ detects >1⁄2HRL = 1.00 % (2 of 201 )

• % GW sites w/ detects = 6.16 % ( 3 1 of 503 )

• % GW sites w/ detects >1⁄2HRL = 0.2 0 % ( 1 of 503 )

• % GW sites w/ detects >HRL = 0.2 0 % ( 1 of 503 )

• % SW sites w/ detects = 73.53 % ( 50 of 68 )

• % SW sites w/ detects >1⁄2HRL = 1.47 % ( 1 of 68 )

• Median detect = 0.0 3 μg/L

• 90%ile detect = 0.04 μg/L

• Max detect = 52 μg/L
1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

NAWQA Domestic Well Water Quality (1991

- 2004)

• % samples w/ detects = 2.1% (38 of 1,772); detections did not exceed 2 μg/L (unknown if detections exceeded HRL)

NAWQA Quality of Public Supply Wells (1993

- 2007; Toccalino et al.)

• MRL = 0.0075 - 0.0793 μg/L

• No detects >1⁄2HRL or >HRL

• % samples w/ detects = 5.28% (31 of 587)

NAWQA National Synthesis (1992

- 2001)

• MRL = 0.060 μg/L

• GW: max detect (5.53 μg/L) from 3,445 mixed, urban and agricultural wells >HRL

• SW: max detect (14.0 μg/L) from 117 mixed, urban and agricultural setting >HRL

NAWQA 3 Study Units (1993

- 1998)

• MRL = 0.02 μg/L

• % samples w/ detects = 22% (185 of 858); no detects >HRLPhase 2 of Protocol for Regulatory Determination 3 April 2014

35 of 84 USGS CWSs Drawing from Streams and Groundwater (2002

- 2005)

• No detects >1⁄2HRL or >HRL

o Phase 1: % GW detects = 3.3% (7 of 215); max detect = 0.166

μg/L

o Phase 1: % SW detects = 30.3% (44 of 145); max detect = 0.44

μg/L

o Phase 2: % GW raw detects = 6.6% (4 of 61); max detect = 0.113

μg/L

o Phase 2: % GW finished detects = 1.7% (1 of 59); max detect = 0.099

μg/L

o Phase 2: % SW raw detects = 42% (38 of 90); max detect = 0.22

μg/L

o Phase 2: % SW finished detects = 24% (21 of 89); max detect = 0.18

μg/L

South Florida Water Management (1998

- 2001)

• MRL = 0.2 - 0.4 μg/L

• % samples w/ detects = 4% (17 of 438); max detect = 1.2 μg/L, >1⁄2HRL

California Department of Pesticide Regulation (2000

- 2001)

• MRL = 0.05 μg/L

• San Joaquin River: 100% (54 samples), >HRL

• Sacramento River: max dete ct = 1.42 μg/L, >HRL

California Department of Pesticide Regulation SURF (2000)

• % samples w/ detects = 57.2% (350 of 612); 95%ile detect = 3.6 μg/L, >HRL

Playa Lake, TX

• % samples w/ detects = 71% (from 32 lakes); mean = 2.7 μg/L, >HRL

Occurrence summary and/or other information:

• No detections in UCMR1 (SS), which is a statistically defined, national sample of 300 PWSs.

• State finished water data and USGS ambient water studyPhase 2 of Protocol for Regulatory Determination 3 April 2014

36 of 84 demonstrates some detections >HRL

16. Methyl Bromide

• CASRN = 74839

• Substance Key = 2601

• A halogenated alkane

• Used as a fumigant fungicide

• Regulated under Montreal Protocol; phased out in 2005 except for “critical use” and other exemptions

Production / Release Data

TRI

- Release 20 10

• Surface water = 1,254 lbs/yr ( 3 states )

• Total = 512,237 lbs/yr ( 16 states)

TRI

- Release 200 8

• Surface water = 71 lbs/yr ( 3 states )

• Total = 489,628 lbs/yr ( 14 states)

TRI

- Release 2006

• Surface water = 361 lbs/yr (2 states)

• Total = 408,252 lbs/yr (16 states)

TRI

- Release 2004

• Surface water = 200 lbs/yr (3 states) Critical Health Endpoint

• Decreased body weight, body weight gain, and food consumption

• NOAEL = 2.2 mg/kg -d ay

• UF = 100

• RfD = 0.0 20 mg/kg

- day

• Non

- cancer HRL = 140 μg/L

Health Assessment Status

• Updated since CCL3

o OPP RED (2006)

• Not classifiable as to human carcinogenicity, group D (1986 cancer guidelines)

Sensitive Populations/Lifestages

• Possibly the young and the elderly Individuals with lung, kidney, or neurological diseases (ATSDR, 1992) Analyzed using HRL of 140 μg/L

National Drinking Water Data

NCOD/UCM Round 1 Finished Water (1988

- 1992)

• MRL unavailable (min detect = 0.07 μg/L)

• No detects >1⁄2HRL or >HRL

• % samples w/ detects = 0.37% (255 of 68,424)

• % PWSs w/ detects = 0.77% (155 of 20,198)

• Median detect = 1.00 μg/L

• 99%ile det e ct = 32.92 μg/L

• Max detect = 43.00 μg/L

NCOD/UCM Round 2 Finished Water (1993

- 1997)

• MRL unavailable (min detect = 0.09 μg/L)

• No detects >1⁄2HRL or >HRL

• % samples w/ detects = 0.26% (235 of 90,731)

• % PWSs w/ detects = 0.75% (175 of 23,328)

• Median detect = 1.60 μg/L

• 99%ile detect = 25.06 μg/L

• Max detect = 38.10 μg/L

Non -N ational Drinking Water Data

State Drinking Water Data (1983

- 2009)

• No detects >1⁄2HRL or >HRL

• % systems w/ detects =

o CA: 1.26% (51 of 4,041)

o FL: 3.70% (1 of 27)

o IL: Not detected from 2 systems

o NC: 0.88% (22 of 2,493)

o OH: 1.62% (41 of 2,531) Does not proceed to phase 3

Rationale: The contaminant likely has low potential for public health concern and has a health data gap.

Health: Health Assessment will not be updated by Fall 2011

Occurrence: The contaminant has national finished water data. While there are some detections at levels of public health concern, based on the draft HRL in the national finished water data, the data is from 1988

- 1997 and the contaminant was phased out for use in 2005. More recent non

- national finished water and ambient/source water data show no or low detections at levels of public health concern, based on the draft HRL.Phase 2 of Protocol for Regulatory Determination 3 April 2014

37 of 84 • Total = 552,208 lbs/yr (17 states)

CUSIUR Production Data

• >10M

- 50M lbs/yr (1998)

• >1M

- 10M lbs/yr (2002)

Fate / Transport

• Expected to be moderately to very mobile in water, based on physical and chemical properties

• Moderately persistent (biodegrades slowly ) ( CCL CIS ) o R9 Tribes: 0.35% (1 of 286)

o SD: Not detected from 281 systems

o TX: 2.05% (116 of 5,660)

o WI ’83

- ’99: 1.50% (29 of 1,929)

o WI ’00

- ’09: 0.53% (6 of 1,123)

Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (2006

- 2007)

• Detected in 1 of 5 CWSs; no detects >H RL

EWG (2004

- 2009)

• 141 PWSs from 23 states w/ detects ; no detects >1⁄2HRL or >HRL

Supplemental Ambient/Source Water Data

NAWQA Ambient Water (1992

- 2001)

• MRLs variable (0.1 - 0.26 μg/L)

• No SW detects

• No GW detects >1⁄2HRL or >HRL

• % GW samples w/ detects = 0.07% (3 of 4,544)

• % GW sites w/ detects = 0.07% (3 of 4,127)

• Median detect = 0.1 μg/L

• 99%ile detect = 0.49 μg/L

• Max detect = 0.5 μg/L

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 33 states

• No GW detects >1⁄2HRL or >HRL

• No SW detects >HRL

• % GW samples w/ detects = 52.84 % ( 4,590 of 8,687 )

• % SW samples w/ detects = 10.05 % ( 1,087 of 1 0 ,8 1 6)

• % SW samples w/ detects >1⁄2HRL = 0. 01 % ( 1 of 10,816 )Phase 2 of Protocol for Regulatory Determination 3 April 2014

38 of 84 • % GW sites w/ detects = 32.43 % (7 57 of 2, 334 )

• % SW sites w/ detects = 29.37 % ( 309 of 1,052 )

• % SW sites w/ detects >1⁄2HRL = 0. 10 % ( 1 of 1,052 )

• Median detect = 0 μg/L

• 90%ile detect = 0.5 μg/L

• Max detect = 110 μg/L
1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

NAWQA Domestic Well Water Quality (1991

- 2004)

• Not detected in 2,269 samples

NAWQA National Focused and Historic VOC Study (1985

- 2001)

• Random Survey (1999

- 2001): detected in 0.21% of samples (2 of 954) , at a maximum concentration of 6.4 μg/L ; no detects >1⁄2HRL or >HRL

• Focused Survey (1999

- 2001): not detected above reporting limit of 0.2 μg/L from 451 samples

• Historical Monitoring (1985

- 1995): not detected in 335 urban wells; detected in 1 of 1,886 rural wells at conc. = 0.5 μg/L

NAWQA Quality of Public Supply Wells (1993

- 2007; Toccalino et al.)

• MRL = 0.074 - 0.26 μg/L

• Not detected in 832 samples

USGS CWSs Drawing from Streams and Groundwater (2002

- 2005)

• Not detected in 221 ground water samples or 147 surface water samples in Phase 1; not detected in 71 raw and 71 finished ground water samples in Phase 2

NAWQA Carbonate Aquifer Study (1993

- 2005)

• Not detected in 793 samples

USGS VOCs in Highway Runoff

• Not detected

Occurrence summary and/or other information:Phase 2 of Protocol for Regulatory Determination 3 April 2014

39 of 84 • No PWSs have detections > 1⁄2 draft HRL or HRL in UCM 1/2.

• National data is pre

- 1997 and the contaminant was phased out in 2005, except for critical use

• No detections >1⁄2 draft HRL or HRL in non

- national finished water

• No or low detections > draft HRL in ambient/source water

• On UCMR 3

17. Methyl tert

- butyl ether (MTBE)

• CASRN = 1634044

• Substance Key = 11918

• An aliphatic ether

• Until recently, was commonly used as an oxygenate and octane booster in gasoline

• Also used in the manufacture of isobutene and as an extraction solvent

Production / Release Data

TRI

- Release 20 10

• Surface water = 800 lbs/yr ( 6 states )

• Total = 1,471,221 lbs/yr ( 35 states)

TRI

- Release 200 8

• Surface water = 1,832 lbs/yr ( 6 states )

• Total = 351,774 lbs/yr ( 34 states)

TRI

- Release 2006

• Surface water = 12,452 Critical Health Endpoint

• Kidney adenomas/carcinomas

• CSF = 0.0018 (mg/kg

- day) -1

• Cancer HRL = 19.4 μg/L

Non

- Cancer Health Effects

• Decreased blood urea nitrogen levels in liver (Robinson et al., 1990)

• LOAEL = 100 mg/kg

- day

• UF = 300

• ATSDR MRL = 0.3 mg/kg

- day

• Non

- cancer HRL = 2,100 μg/L

Health Assessment Status

• 1999 OEHHA (CA) – Cancer

• 1996 ATSDR – Non

- cancer

• On the 2012 IRIS Agenda

Sensitive Populations/Lifestages

• None identified Analyzed using HRL of 19.4 μg/L

National Drinking Water Data

UCMR 1 Finished Water Assessment Monitoring (2001

- 2003)

• MRL = 5 μg/L

• % samples w/ detects = 0.08% (26 of 33,768)

• % samples w/ detects >1⁄2HRL = 0.03% (11 of 33,768)

• % samples w/ detects >HRL = 0.01% (5 of 33,768)

• % PWSs w/ detects = 0.49% (19 of 3,871)

• % PWSs w/ detects >1⁄2HRL = 0.28% (11 of 3,871)

• % PWSs w/ detects >HRL = 0.13% (5 of 3,871)

• Median detect = 9.2 μg/L

• 99%ile detect = 48.8 μg/L

• Max detect = 49.0 μg/L

Non -N ational Drinking Water Data

State Drinking Water Data (1991

- 2009)

• % systems w/ detects =

o CA: 3.39% (150 of 4, 419)

o FL: 22.58% (7 of 31)

o IL: 2.24% (26 of 1,161)

o OH: 0.46% (6 of 1,306)

o R9 Tribes: 0.46% (1 of 219)

o TX: 0.72% (41 of 5,660)

o WI ’91

- ’99: 1.97% (4 of 203)

o WI ’00

- ’09: 2.93% (27 of 920) Does not proceed to phase 3

Rationale: The contaminant has no or low detections based on national finished water data but difficult to assess whether at public health concern due to health data gap.

Health: IRIS health assessment will not be completed by Fall 2011

Occurrence: Low percentage of detections > draft HRL in national finished water data which indicates that it is potentially not occurring at levels of public health

concernPhase 2 of Protocol for Regulatory Determination 3 April 2014

40 of 84 lbs/yr (14 states)

• Total = 1,017,089 lbs/yr (41 states)

TRI

- Release 2004

• Surface water = 40,171 lbs/yr (17 states)

• Total = 2,087,675 lbs/yr (42 states)

CUSIUR Production Data

• >1B lbs/yr (1998, 2002)

• ≥ 1B lbs/yr (2006)

Fate / Transport

• Expected to be moderately to highly mobile in water, based on physical and chemical properties

• Moderately persistent in the environment (biodegrades slowly ) ( CCL CIS ) • % systems w/ detects >1⁄2HRL =

o CA: 0.84% (37 of 4,419)

o FL: 3.23% (1 of 31)

o IL: 0.17% (2 of 1,161)

o OH: Not detected from 1,306 systems

o R9 Tribes: 0.46% (1 of 219)

o TX: 0.11% (6 of 5,660)

o WI ’91

- ’99: Not detected from 203 systems

o WI ’00

- ’09: 0.43% (4 of 920)

• % systems w/ detects >HRL =

o CA: 0.43% (19 of 4,419)

o FL: 3.23% (1 of 31)

o IL: Not detected from 1,161 systems

o OH: Not detected from 1,306 systems

o R9 Tribes: Not detected from 219 systems

o TX: 0.05% (3 of 5,660)

o WI ’91

- ’99: Not detected from 203 systems

o WI ’00

- ’09: 0.43% (4 of 920)

Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (2006

- 2007)

• Detected in 1 CWS; max detect = 7.7 μg/L, no detects >1⁄2HRL or >HRL

CWSS (2006)

• % PWSs w/ detects = 1.06% (1 of 94)

• % samples w/ detects = 35% (7 of 20); max detect = 5 μg/L, no

detects > 1⁄2HRL or >HRL

EWG (2004

- 2009)

• At least 35 PWSs from 14 states w/ detects >1⁄2HRL

Supplemental Ambient/Source Water Data

NAWQA Ambient Water (1992

- 2001)Phase 2 of Protocol for Regulatory Determination 3 April 2014

41 of 84 • MRLs variable (most within 0.1 – 0.2 μg/L)

• % GW samples w/ detects = 9.09% (422 of 4,645)

• % GW samples w/ detects >1⁄2HRL = 1.83% (85 of 4,645)

• % GW samples w/ detects >HRL = 1.74% (81 of 4,645)

• % SW samples w/ detects = 46.22% (648 of 1,402)

• % SW samples w/ detects >1⁄2HRL = 1.21% (17 of 1,402)

• % SW samples w/ detects >HRL = 1.14% (16 of 1,402)

• % GW sites w/ detects = 7.50% (311 of 4,146)

• % GW sites w/ detects >1⁄2HRL = 0.82% (34 of 4,146)

• % GW sites w/ detects >HRL = 0.75% (31 of 4,146)

• % SW sites w/ detects = 62.09% (113 of 182)

• % SW sites w/ detects >1⁄2HRL = 1.10% (2 of 182)

• % SW sites w/ detects >HRL = 0.55% (1 of 182)

• Median de tect = 0.3 μg/L

• 99%ile detect = 1,800 μg/L

• Max detect = 23,000 μg/L

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 1 8 states

• % GW samples w/ detects = 46.21 % ( 1,324 of 2,865 )

• % GW samples w/ detects >1⁄2HRL = 2.58 % (74 of 2,865 )

• % GW samples w/ detects >HRL = 2.06 % (59 of 2,865 )

• % SW samples w/ detects = 26.73 % ( 472 of 1,7 66 )

• % SW samples w/ detects >1⁄2HRL = 0.5 7 % (10 of 1,7 66 )

• % SW samples w/ detects >HRL = 0.2 3 % (4 of 1,7 66 )

• % GW sites w/ detects = 37.62 % ( 395 of 1,050 )

• % GW sites w/ detects >1⁄2HRL = 2 .48% (26 of 1,050 )

• % GW sites w/ detects >HRL = 1.81 % (19 of 1,050 )

• % SW sites w/ detects = 18.68 % ( 65 of 348)

• % SW sites w/ detects >1⁄2HRL = 2.59% (9 of 348)

• % SW sites w/ detects >HRL = 1.15% (4 of 348)

• Median detect = 0 μg/ L

• 90%ile detect = 2.55 μg/L

• Max detect = 13,000 μg/LPhase 2 of Protocol for Regulatory Determination 3 April 2014

42 of 84 1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

NAWQA National Focused and Historic VOC Study (1985

- 2001)

• Random Survey (1999

- 2001): detected in 8.7% of 934 samples; one detect >HRL

• Focused Survey (1999

- 2001): detected at 55.5% of 134 sites, max conc. in ground water >HRL

• Historical Monitoring (1985

- 1995): detected at 16.9% of 225 urban wells and 3.4% of 1,312 rural wells; max conc. = 10,000 μg/L, >HRL

USGS VOCs in Highway Runoff (1991

- 1995)

• Detected in 3 of 3 stormwater studies, w/ reported max conc. of 8.7 μg/L, no detects > 1⁄2HRL or >HRL

USGS CWSs Drawing from Streams and Groundwater (2002

- 2005)

• In Phase 1, no detects >1⁄2HRL or >HRL in 221 GW samples and 147 SW samples (max conc. = 3.44 μg/L)

• In Phase 2, no detects >1⁄2HRL or >HRL in 71 GW samples and 95 raw and 94 finished SW samples.

NAWQA Quality of Public Supply Wells (1993

- 2007; Toccalino et al.)

• MRL = 0.05 - 0.2 μg/L

• No detects >HRL

• % samples w/ detects = 13.82% (115 of 832)

• % samples w/ detects >1⁄2HRL = 0.12% (1 of 832)

NAWQA Domestic Well Water Quality (1991

- 2004)

• MRL = 0.08

- 0.2 μg/L

• % wells w/ detects = 4.3% (97 of 2,268); at least one detect >HRL

NAWQA Carbonate Aquifer Study (1993

- 2005)

• In 793 samples, max conc. = 51 μg/L, >HRL

CDC Fourth National Report (2003

- 2004)

• 95%iles <LOD in 1,307 blood samplesPhase 2 of Protocol for Regulatory Determination 3 April 2014

43 of 84 Occurrence summary and/or other information:

• Some detections > best available HRL in UCMR1 as well as supplemental state drinking water and USGS ambient water data

18. Metolachlor

• CASRN = 51218452

• Substance Key = 35270

• An acetanilide pesticide

• A broad spectrum herbicide for general weed control. Initially registered in 1976 for use on turf, it is now also registered for use on corn, cotton, peanuts, pod crops, potatoes, safflowers, sorghum, soybeans, stone fruits, tree nuts, nonbearing citrus, nonbearing grapes, cabbage, certain peppers, buffalo grass, guymon bermudagrass for seed production, nurseries, hedgerows/fencerows, and landscape plantings

Production / Release Data

NCFAP Total Pesticide Application 1997

• 67,336,211 lbs/yr (48 states)

Pesticide Industry Sales and Usage Report : Metolachlor

• 1987: 45M

- 50M lbs

• 1997: 63M

- 69M lbs

• 1999: 26M

- 30M lbs Critical Health Endpoint

• Decreased body weight gain ( Hazelette, 1989)

• NOEL = 9.7 mg/kg

- day

• UF = 100

• RfD = 0.1 mg/kg

- day

• Non

- cancer HRL = 700 μg/L

Health Assessment Status

• OPP RED (1995)

• Possible human carcinogen, group C (1986 cancer guidelines)

Sensitive Populations/Lifestages

• None identified Analyzed using HRL of 700 μg/L

National Drinking Water Data

UCMR 2 Finished Water Screening Survey (2008

- 2010)

• MRL = 1 μg/L

• No detects >1⁄2HRL or >HRL

• % samples w/ detects = 0.03% (3 of 11,137)

• % PWSs w/ detects = 0.25% (3 of 1,198)

• Median detect = 1.40 μg/L

• 99%ile detect = 2.71 μg/L

• Max detect = 2.73 μg/L

NCOD/UCM Round 2 Finished Water, 20

- State Cross

- Section (1993

- 1997)

• MRLs variable (min detect = 0.01 μg/L)

• No detects >1⁄2HRL or >HRL

• % samples w/ detects = 0.62% (211 of 34,112)

• % PWSs w/ detects = 0.89% (116 of 13,007)

• Median detect = 0.57 μg/L

• 99%ile detect = 7.1 μg/L

• Max detect = 13.8 μg/L

Non -N ational Drinking Water Data

State Drinking Water Data (1984

- 2008)

• No detects >1⁄2HRL or >HRL

• % systems w/ detects =

o CA: 0.69% (15 of 2,172)

o FL: Not detected from 6 systems

o IL: 1.94% (17 of 875) Does not proceed to phase 3

Rationale: While metolachlor has no or low potential for public health concern, based on national finished water data, it might be considered as a group along with other chloroacetanilides and/or their degradates in the future. And at this time, the Agency does not have a health assessment for the degradates (i.e., a health data gap).

Health: Health assessments for the degradates will no t be completed by Fall 2011

Occurrence: Few detections for Metolachlor (parent) in national finished water dataPhase 2 of Protocol for Regulatory Determination 3 April 2014

44 of 84 • 2001: 15M

- 22M lbs

Pesticide Industry Sales and Usage Report : S- Metolachlor

• 1999: 16 M- 19 M lbs

• 2001: 20M

- 24M lbs

• 2003: 28M

- 33M lbs

• 2005: 27 M- 32M lbs

• 2007: 30 M- 35M lbs

RED 1995

• ~58.7M lbs active ingredient used annually between 1987

- 1993

Fate / Transport

• Moderately to very mobile in soil (RED)

• Subject to biodegradation and adsorption to suspended solids and sediment in water o NC: 0.08% (2 of 2,477)

o OH: 0.73% (6 of 821)

o R9 Tribes: Not detected from 225 systems

o SD: Not detected from 255 systems

o TX: 1.78% (40 of 2,252)

o WI ’83

- ’99: 0.77% (9 of 1,175)

o WI ’00

- ’09: 0.77% (7 of 915)

Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (2006

- 2007)

• Not detected >1⁄2HRL or >HRL in 5 CWSs

CWSS (2000)

• No detects >1⁄2HRL or >HRL

CWSS (2006)

• % PWSs w/ detects = 3.19% (3 of 94); no detects >1⁄2HRL or >HRL

EWG (2004

- 2009)

• 115 PWSs from 20 states w/ detects; no detects >1⁄2HRL or >HRL

PDP Raw and Finished Water (2001

- 2009 )

• Max detect in finished water = 2.031 μg/L, <1⁄2 HRL

• Max detect in raw water = 2.000 μg/L, <1⁄2 HRL

• % samples w/ detects = 4 2. 17 % ( 2.433 of 5,770 ); no detects >1⁄2HRL or >HRL

PMP Raw & Finished Water (1999)

• No max conc. >1⁄2HRL or >HRL

Other studies w/ no detects >1⁄2HRL or >HRL

• National Pesticide Survey (1988

- 1990)

• Wisconsin GW Study (1999

- 2000)Phase 2 of Protocol for Regulatory Determination 3 April 2014

45 of 84 Supplemental Ambient/Source Water Data

NAWQA Ambient Water (1992

- 2001)

• MRLs variable (0.002 – 0.006 μg/L)

• No GW or SW detects >1⁄2HRL or >HRL

• % GW samples w/ detects = 12.28% (750 of 6,108)

• % SW samples w/ detects = 68.87% (10,767 of 15,634)

• % GW sites w/ detects = 11.44% (597 of 5,217)

• % SW sites w/ detects = 62.63% (1,220 of 1,984)

• Median detect = 0.03 μg/L

• 99%ile detect = 6.71 μg/L

• Max detect = 77.6 μg/L

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 2 7 states

• No detects >1⁄2HRL or >HRL

• % GW samples w/ detects = 8.40 % ( 260 of 3,094 )

• % SW samples w/ detects = 37.03 % ( 13,688 of 36,967 )

• % GW sites w/ detects = 8.89 % ( 84 of 945 )

• % SW sites w/ detects = 58.99 % (1, 512 of 2,563 )

• Minimum detect = 0. 16 μg/L

• 90%ile detect = 1.3 7 μg/L

• Max detect = 1 33.20 μg/L
1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

NREC Ambient Water

• MRL unavailable

• % SW sites w/ detects = 8.76%; no detects >1⁄2HRL or >HRL

• % GW sites w/ detects = 1.23%; no detects >1⁄2HRL or >HRL

NAWQA National Synthesis (1992

- 2001)

• LT

- MDL = 0.006 μg/L

• No max. detects >1⁄2HRL or >HRLPhase 2 of Protocol for Regulatory Determination 3 April 2014

46 of 84 NAWQA Domestic Well Water Quality (1991

- 2004)

• % samples w/ detects = 6.9% (174 of 2,540); no detects >1⁄2HRL or >HRL

NAWQA Carbonate Aquifer Study (1993

- 2005)

• % samples w/ detects = 14.9% (153 of 1,027); no detects >1⁄2HRL or >HRL

NAWQA Quality of Public Supply Wells (1993

- 2007; Toccalino et al.)

• MRL = 0. 002 - 0.006 μg/L

• No detects >1⁄2HRL or >HRL

• % samples w/ detects = 8.62% (75 of 870)

USGS CWSs Drawing from Streams and Groundwater (2002

- 2005)

• No detects >1⁄2HRL or >HRL

o Phase 1 % samples w/ GW detects = 10.9% (24 of 221); max

detect = 3.58 μg/L

o Phase 1 % samples w/ SW detects = 51.4% (75 of 146); max

detect = 2.93 μg/L

o Phase 2 % GW raw detects = 13.0% (8 of 64)

o Phase 2 % GW finished detects = 11.0% (7 of 65)

o Phase 2 % SW raw detects = 59.0% (53 of 90)

o Phase 2 % SW finished detects = 54.0% (47 of 87)

Pesticides in GW Database (1971

- 1991)

• % wells w/ detects = 0.96% (213 of 22,255); no detects >1⁄2HRL or >HRL

• % states w/ detects = 68.97% (20 of 29)

Acetochlor Registration Partnership (1995

- 2001)

• % wells w/ detects in GW study = 16.48% (30 of 182)

• % samples w/ detects in SW study = 53%

Iowa Well Water Study (2006

- 2008)

• % samples w/ detects = 1.92% (9 of 469); no detects >1⁄2HRL or >HRL

Iowa SDWA Compliance (1988

- 1995)Phase 2 of Protocol for Regulatory Determination 3 April 2014

47 of 84 • % samples w/ detects = 16%; max detect = 9.4 μg/L, no detects

> 1⁄2HRL or >HRL

Other studies w/ no detects >1⁄2HRL or >HRL

• Pesticides/Metabolites - Suffolk County, NY (1998)

• Metolachlor/Metabolites in Tile Drain & Stream Runoff - Canajoharie Creek Watershed (1997)

CDC Fourth National Report (2003

- 2004)

• 95%iles <LOD in 2,538 urine sam ples

Occurrence summary and/or other information:

• Few (3) detections, none >HRL in recent national data (UCMR 2); Metolachlor (parent) is potentially not occurring at levels of public health concern

• Frequent detections in ambient water with some detections >HRL

• Metolachlor and other chloroacetanilides may be considered as a group 19. Metolachlor ethanesulfonic acid (ESA)

• CASRN = 171118095

• Substance Key = 79218

• A degradate of metolachlor

• See also parent compound

Production / Release Data Not produced commercially

Fate / Transport

• Expected mobility in water: metolachlor ESA > metolachlor OA > metolachlor

• May be very persistent in Critical Health Endpoint

• Parent (Metolachlor) is surrogate

• Decreased body weight gain ( Hazelette, 1989)

• NOEL = 9.7 mg/kg

- day

• UF = 100

• RfD = 0.1 mg/kg

- day

• Non

- cancer HRL = 700 μg/L

Non

- Cancer Health Effects

• OPP supplemental data

• No biologically significant effects

• NOEL ≥ 1,000 mg/kg

- day

• Non

- cancer HRL > 7,000 μg/L

Health Assessment Status

• Parent compound [OPP RED 1995] Analyzed using HRL of 700 μg/L

National Drinking Water Data

UCMR 2 Finished Water Screening Survey (2008

- 2010)

• MRL = 1 μg/L

• No detects >1⁄2HRL or >HRL

• % samples w/ detects = 0.47% (52 of 11,100)

• % PWSs w/ detects = 1.59% (19 of 1,198)

• Median detect = 1.44 μg/L

• 99%ile detect = 3.63 μg/L

• Max detect = 3.95 μg/L

Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (2007)

• Not detected >1⁄2HRL or >HRL in 1 CWS Does not proceed to phase 3

Rationale: While metolachlor ESA has no or low detections based on national finished water data, there is no health assessment for the ESA degradate and it difficult to assess whether it is occurring at levels of concern. Also, metolachlor ESA might be considered as a group along with other chloroacetanilides and/or their degradates in the future.

Health: Health assessment for Metolachlor ESA (degradate) will not be completed by Fall 2011Phase 2 of Protocol for Regulatory Determination 3 April 2014

48 of 84 ground water Sensitive Populations/Lifestages

• None identified CWSS (2006)

• % PWSs w/ detects = 1.16% (1 of 86); no detects >1⁄2HRL or >HRL

PDP Raw and Finished Water (2001

- 2009 )

• Max detect in finished water = 2.24 μg/L, <1⁄2 HRL

• Max detect in raw water = 3.603 μg/L, <1⁄2 HRL

• % samples w/ detects = 65

. 13 % (3, 192 of 4 ,901 ); no detects >1⁄2HRL or >HRL

Other studies w/ no detects >1⁄2HRL or >HRL

• Wisconsin GW Study (1999

- 2000)

Supplemental Ambient/Source Water Data

USGS CWSs Drawing from Streams and Groundwater (2002

- 2005)

• No detects >1⁄2HRL or >HRL

o Phase 1 % GW detects = 28.8% (21 of 73); max detect = 2.72

μg/L

o Phase 1 % SW detects = 69.2% (27 of 39); max detect = 2.07

μg/L

o Phase 2 % GW raw detects = 47.0% (15 of 32)

o Phase 2 % GW finished detects = 41.0% (13 of 32)

o Phase 2 % SW raw detects = 68.0% (33 of 49)

o Phase 2 % SW finished detects = 59.0% (28 of 48)

Acetochlor Registration Partnership (1999

- 2001)

• % wells w/ detects in GW study = 58.24% (106 of 182)

• % samples w/ detects in SW study = 56%

Iowa Well Water Study (2006

- 2008)

• % samples w/ detects = 33.05% (156 of 472); no detects >1⁄2HRL or >HRL

Other studies w/ no detects >1⁄2HRL or >HRL

• Pesticides/Metabolites

- Suffolk County, NY (1998) Occurrence: No detections for Metolachlor ESA (degradate) in national finished water data at levels of public health concern based on the draft HRLPhase 2 of Protocol for Regulatory Determination 3 April 2014

49 of 84 • Metolachlor/Metabolites in Tile Drain & Stream Runoff - Canajoharie Creek Watershed (1997)

Occurrence summary and/or other inform ation:

• No detections for Metolachlor ESA > parent (Metolachlor) HRL in national data (UCMR 2) as well as supplemental drinking water and ambient water data

20. Metolachlor oxanilic acid (OA )

• CASRN = 152019733

• Substance Key = 79220

• A degradate of metolachlor

• See also parent compound

Production / Release Data Not produced commercially

Fate / Transport

• Expected mobility in water: metolachlor ESA > metolachlor OA > metolachlor

• May be very persistent in ground water Critical Health Endpoint

• Parent (Metolachlor) is surrogate

• Decreased body weight gain ( Hazelette, 1989)

• NOEL = 9.7 mg/ kg

- day

• UF = 100

• RfD = 0.1 mg/kg

- day

• Non

- cancer HRL = 700 μg/L

Non

- Cancer Health Effects

• OPP supplemental data

• No biologically significant effects

• NOEL ≥ 1,000 mg/kg

- day

• Non

- cancer HRL > 7,000 μg/L

Health Assessment Status

• Parent compound [OPP RED 1995]

Sensitive Populations/Lifestages

• None identified Analyzed using HRL of 700 μg/L

National Drinking Water Data

UCMR 2 Finished Water Screening Survey (2008

- 2010)

• MRL = 2 μg/L

• No detects >1⁄2HRL or >HRL

• % samples w/ detects = 0.03% (3 of 11,100)

• % PWSs w/ detects = 0.08% (1 of 1,198)

• Median detect = 3.08 μg/L

• 99%ile detect = 3.53 μg/L

• Max detect = 3.54 μg/L

Supplemental Drinking Water Data Recent CCRs from 26 CWSs that serve >1M (2007)

• Not detected >1⁄2HRL or >HRL in 1 CWS

CWSS (2006)

• % PWSs w/ detects = 1.16% (1 of 86); no detects >1⁄2HRL or >HRL

PDP Raw and Finished Water (2001

- 2009 )

• Max detect in finished water = 4.42 μg/L, <1⁄2 HRL

• Max detect in raw water = 1.5 μg/L, <1⁄2 HRL

• % samples w/ detects = 4 5. 21 % ( 2, 251 of 4, 979 ); no detects >1⁄2HR L or >HRL

Other studies w/ no detects >1⁄2HRL or >HRL Does not proceed to phase 3

Rationale: While Metolachlor OA has no or low detections based on national finished water data, there is no health assessment for the OA degradate and it difficult to assess whether it is occurring at levels of concern. Also, metolachlor OA might be considered as a g roup along with other chloroacetanilides and/or their degradates in the future.

Health: Health assessment for Metolachlor OA (degradate) will not be completed by Fall 2011

Occurrence: No detections for Metolachlor OA (degradate) in national finished w ater data at levels of public health concern based on the draft HRLPhase 2 of Protocol for Regulatory Determination 3 April 2014

50 of 84 • Wisconsin GW Study (1999

- 2000)

Supplemental Ambient/Source Water Data

USGS CWSs Drawing from Streams and Groundwater (2002

- 2005)

• No detects >1⁄2HRL or >HRL

o Phase 1 % GW detects = 15.1% (11 of 73); max detect = 2.96

μg/L

o Phase 1 % SW detects = 66.7% (26 of 39); max detect = 1.47

μg/L

o Phase 2 % GW raw detects = 38.0% (12 of 32)

o Phase 2 % GW finished detects = 34.0% (11 of 32)

o Phase 2 % SW raw detects = 77.0% (38 of 49)

o Phase 2 % SW finished detects = 59.0% (28 of 48)

Acetochlor Registration Partnership (1999

- 2001)

• % wells w/ detects in GW study = 34.62% (63 of 182)

• % samples w/ detects in SW study = 57%

Iowa Well Water Study (2006

- 2008)

• % samples w/ detects = 8.26% (39 of 472); no detects >1⁄2HRL or >HRL

Othe r studies w/ no detects >1⁄2HRL or >HRL

• Pesticides/Metabolites - Suffolk County, NY (1998)

• Metolachlor/Metabolites in Tile Drain & Stream Runoff - Canajoharie Creek Watershed (1997)

Occurrence summary and/or other information:

• No detections for Metolachlor OA > parent (Metolachlor) HRL in national data (UCMR 2) as well as supplemental drinking water and ambient water data

21. Molinate

• CASRN = 2212671

• Substance Key = 12912

• An azepine pesticide, used Critical Health Endpoint

• Reproductive toxicity

• NOEL = 0.2 mg/kg

- day

• UF = 100 Analyzed using HRL of 14 μg/L

National Drinking Water Data Does not proceed to phase 3

Rationale: The contaminant likely has no orPhase 2 of Protocol for Regulatory Determination 3 April 2014

51 of 84 as an herbicide

• Uses cancelled in 2004; phase

- out scheduled to be complete in 2009

Production / Release Data

TRI

- Release 2006

• Surface water = 4 lbs/yr (1 state)

• Total = 799 lbs/yr (1 state)

TRI

- Release 2004

• Surface water = 115 lbs/yr (1 state)

• Total = 2,089 lbs/yr (2 states)

NCFAP Total Pesticide Application 1997

• 3,669,398 lbs/yr (6 states)

Fate / Transport

• Expected to be moderately mobile in water, based on physical and chemical properties

• Subject to biodegradation and volatilization • RfD = 0.002 mg/kg

- day

• Non

- cancer HRL = 14 μg/L

Health Assessment Status

• IRIS 1988

• An OPP RED was in process but will not be completed due to cancellation of molinate

Sensitive Populations/Lifestages

• Fetuses UCMR 1 Finished Water Assessment Monitoring (2001

- 2003)

• MRL = 0.9 μg/L

• No detects >1⁄2 HRL or >HRL

• % PWSs w/ detects = 0.03% (1 of 3,873)

• % samples w/ detects = 0.003% (1 of 33,799)

• Median detect = 5.7 μg/L

• 99%ile detect = 5.7 μg/L

• Max detect = 5.7 μg/L

Non -N ational Drinking Water Data

State Drinking Water Data (1995

- 2007)

• No detects 1⁄2 HRL or >HRL

• % systems w/ detects =

o CA: 0.13% (3 of 2,280)

o IL: Not detected from 85 systems

o OH: Not detected from 24 systems

Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (2006

- 2007)

• Not detected in 3 CWSs in NY

EWG (2004

- 2009)

• 1 PWS in 1 state w/ detects; no detects >1⁄2HRL or >HRL

PDP Raw and Finished Water (2001

- 2009 )

• Not detected in 3, 270 samples

PMP Raw Water (1999)

• % samples w/ detects = 0.3% (1 of 333); max detect = 0.004 μg/L, no detects > 1⁄2HRL or >HRL low potential for public health

concern

Health: Available health assessment

Occurrence: No detections in national or non

national finished water data at levels of public health concern based on HRLPhase 2 of Protocol for Regulatory Determination 3 April 2014

52 of 84 Supplemental Ambient/Source Water Data

NAWQA Ambient Water (1992

- 2001)

• MRLs variable (most are 0.004 μg/L)

• No GW detects >1⁄2HRL or >HRL

• % GW samples w/ detects = 0.39% (24 of 6,080)

• % SW samples w/ detects = 5.38% (800 of 14,876)

• % SW samples w/ detects >1⁄2HRL = 0.30% (45 of 14,876)

• % SW samples w/ detects >HRL = 0.21% (31 of 14,876)

• % GW sites w/ detects = 0.46% (24 of 5,211)

• % SW sites w/ detects = 5.03% (96 of 1,907)

• % SW sites w/ detects >1⁄2HRL = 1.10% (21 of 1,907)

• % SW sites w/ detects >HRL = 0.68% (13 of 1,907)

• Median detect = 0.0372 μg/L

• 99%ile detect = 47.9 μg/L

• Max detect = 200 μg/L

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 13 states

• No GW d etects in 33 samples from 14 sites

• % SW samples w/ detects = 30.18 % ( 457 of 1,514 )

• % SW samples w/ detects >1⁄2HRL = 1.59 % ( 24 of 1,514 )

• % SW samples w/ detects >HRL = 0. 86 % ( 1 3 of 1,514 )

• % SW sites w/ detects = 31.47 % ( 203 of 645 )

• % SW sites w/ detects > 1⁄2HRL = 3.41 % ( 22 of 645 )

• % SW sites w/ detects >HRL = 2.02 % ( 1 3 of 645 )

• Median detect = 0.05 μg/L

• 90%ile detect = 2.68 μg/L

• Max detect = 332.65 μg/L
1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

National Pesticide Survey (1988

- 1990)

• MRL = 0.18 μg/L

• Not detected in 566 CWS wells and 783 rural domestic wellsPhase 2 of Protocol for Regulatory Determination 3 April 2014

53 of 84 NAWQA Carbonate Aquifer Study (1993

- 2005)

• Not detected in 992 samples

NAWQA Domestic Well Water Quality (1991

- 2004)

• % samples w/ detects = 0.1% (2 of 2,539); no detects >1⁄2HRL or >HRL

NAWQA Quality of Public Supply Wells (1993

- 2007; Toccalino et al.)

• MRL = 0.0008 - 0.004 μg/L

• No detects >1⁄2HRL or >HRL

• % samples w/ detects = 0.47% (3 of 635)

NAWQA National Synthesis (1992

- 2001)

• MRL = 0.001 μg/L

• GW: no max detects >1⁄2HRL or >HRL

• SW: max detect from agricultural sites (200 μg/L) >HRL; max detect from mixed land use sites (1.57 μg/L) no detects > 1⁄2HRL or >HRL

Occurrence summary and/or other information:

• One detection, none >HRL in national finished water data (UCMR1)

• Few detections in CA drinking water data, none >HRL

• Detections in ambient water data; some >HRL

• Uses cancelled in 2004; phase

- out scheduled to be complete in 2009 22. Molybdenum

• CASRN = 7439987

• Substance Key = 18825

• A naturally

- occurring element

• Commonly used form, Molybdenum trioxide, is used as a chemical reagent

Production / Release Data Critical Health Endpoint (s)

• Gout

- like symptoms and increased serum uric acid (Koval'skiy et al., 1961 in IRIS 1991 )

• LOAEL = 0.14 mg/kg

- day

• UF = 30

• RfD = 0.005 mg/kg

- day

• Non

- cancer HRL = 35 μg/L

• Female r eproductive effects (Fungwe et al., 1990 in IOM 2001 ) Analyzed using HRLs of 35 μg/L and 200 μg/L

Analysis at HRL of 35 μg/L :

National Drinking Water Data

NIRS Finished Water [GW only] (1984

- 1986)

• MRL = 6 μg/L

• % PWSs w/ detects = 7.79% (77 of 989)

• % PWSs w/ detects >1⁄2HRL = 2.43% (24 of 989) Does not proceed to phase 3

Rationale: The contaminant likely has no or low potential for public health concern, but has a health data gap.

Health: Health assessment will not be updated by Fall 2011

Occurrence:Phase 2 of Protocol for Regulatory Determination 3 April 2014

54 of 84 TRI

- Release 20 10

• Surface water = 40,058 lbs/yr (15 states )

• Total = 1,416,893 lbs/yr ( 33 states)

TRI

- Release 200 8

• Surface water = 45,828 lbs/yr (16 states )

• Total = 1,495,177 lbs/yr ( 30 states)

TRI

- Release 2006

• Surface water = 40,030 lbs/yr (20 states)

• Total = 2,454,437 lbs/yr (36 states)

TRI

- Release 2004

• Surface water = 36,579 lbs/yr (18 states)

• Total = 2,115,011 lbs/yr (36 states)

Fate / Transport

• Ionic species expected to be mobile in most soils (HSDB)

• Persistent in the environment, though the form may change (CCL CIS ) • NOAEL = 0.9 mg/kg

- day

• UF = 30

• RfD eq. = 0.03 mg/kg

- day

• Non

- cancer HRL = 200 μg/L

Health Assessment Status

• IRIS (1991)

• Not classifiable as to human carcinogenicity, group D (1986 cancer guidelines)

• Updated since CCL3

o NAS (IOM 2001 pgs. 436

- 437 )

Sensitive Populations/Lifestages

• People susceptible to gout • % PWSs w/ detects >HRL = 0.61% (6 of 989)

• Median detect = 10 μg/L

• 99%ile detect = 106 μg/L

• Max detect = 181 μg/L

Non -N ational Drinking Water Data

State Drinking Water Data (1995

- 2007)

• % systems w/ detects =

o CA: 66.46% (107 of 161)

o IL: 17.23% (149 of 865)

o OH: 50.00% (13 of 26)

o WI ’00

- ’09: Not detected from 1 system

• % systems w/ detects >1⁄2HRL =

o CA: 11.80% (19 of 161)

o IL: 13.99% (121 of 865)

o OH: 15.38% (4 of 26)

• % systems w/ detects >HRL =

o CA: 3.73% (6 of 161)

o IL: 3.35% (29 of 865)

o OH: 7.69% (2 of 26)

Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (2007)

• Detected in 2 CWSs; max detect in 1 CWS >HRL

CWSS (2006)

• % PWSs w/ detects = 6.90% (4 of 58); max detect = 203 μg/L, >HRL

EWG (2004

- 2009)

• At least 21 PWSs in 4 states w/ detects >HRL, and at least 22 PWSs in 4 states w/ detects >1⁄2HRL No detections in national or non

national finished water data at levels of public health concern based on the draft HRLPhase 2 of Protocol for Regulatory Determination 3 April 2014

55 of 84 Supplemental Ambient/Source Water Data

NAWQA Ambient Water (1992

- 2001)

• MRLs variable (most within 0.2 – 1 μg/L)

• % GW samples w/ detects = 55.57% (1,807 of 3,252)

• % GW samples w/ detects >1⁄2HRL = 3.78% (123 of 3,252)

• % GW samples w/ detects >HRL = 1.88% (61 of 3,252)

• % SW samples w/ detects = 47.14% (1,120 of 2,376)

• % SW samples w/ detects >1⁄2HRL = 2.78% (66 of 2,376)

• % SW samples w/ detects >HRL = 0.42% (10 of 2,376)

• % GW sites w/ detects = 56.51% (1,641 of 2,904)

• % GW sites w/ detects >1⁄2HRL = 4.03% (117 of 2,904)

• % GW sites w/ detects >HRL = 1.96% (57 of 2,904)

• % SW sites w/ detects = 60.56% (238 of 393)

• % SW sites w/ detects >1⁄2HRL = 4.33% (17 of 393)

• % SW sites w/ detects >HRL = 1.02% (4 of 393)

• Median detect = 3 μg/L

• 99%ile detect = 55.41 μg/L

• Max detect = 4,732.80 μg/L

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 3 7 states

• % GW samples w/ detects = 44.46 % ( 987 of 2,220 )

• % GW samples w/ detects >1⁄2HRL = 13.47 % ( 299 of 2,220 )

• % GW samples w/ detects >HRL = 10.63 % ( 236 of 2,220 )

• % SW samples w/ detects = 42.29 % ( 26,511 of 62,686 )

• % SW samples w/ detects >1⁄2HRL = 9.89 % ( 6,200 of 62,686 )

• % SW samples w/ detects >HRL = 3.85 % (2, 415 of 62,686 )

• % GW sites w/ detects = 54.94 % ( 384 of 699 )

• % GW sites w/ detects >1⁄2HRL = 17.45 % ( 122 of 699 )

• % GW sites w/ detects >HRL = 16.17 % ( 113 of 699 )

• % SW sites w/ detects = 37. 99 % ( 5,754 of 15,145 )Phase 2 of Protocol for Regulatory Determination 3 April 2014

56 of 84 • % SW sites w/ detects >1⁄2HRL = 9.84 % (1, 491 of 15,145 )

• % SW sites w/ detects >HRL = 4.27 % ( 647 of 15,145 )

• Median detect = 4 μg/L

• 90%ile detect = 33 μg/L

• Max detect = 75,000 μg/L
1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

NAWQA Quality of Public Supply Wells (1993

- 2007; Toccalino et al.)

• MRL = 0.06 - 1 μg/L

• % samples w/ detects = 77.23% (485 of 628)

• % samples w/ detects >1⁄2HRL = 2.23% (14 of 628)

• % samples w/ detects >HRL = 0.64% (4 of 628)

NAWQA Domestic Well Water Quality (1991

- 2004)

• 0.55% of wells exceeded 40 μg/L, >HRL

U.S. Glacial Aquifer Study (1991

- 2003)

• % samples w/ detects =71.8% (608 of 847)

• Max detect (304 μg/L) >HRL

Analysis at HRL of 200 μg/L:

National Drinking Water Data

NIRS Finished Water [GW only] (1984

- 1986)

• MRL = 6 μg/L

• No detects >HRL

• % PWSs w/ detects = 7.79% (77 of 989)

• Median detect = 10 μg/L

• 99%ile detect = 106 μg/L

• Max detect = 181 μg/L

Non

- N ational Drinking Water DataPhase 2 of Protocol for Regulatory Determination 3 April 2014

57 of 84 State Drinking Water Data (1995

- 2007)

• No detects >HRL

• % systems w/ detects =

o CA: 66.46% (107 of 161)

o IL: 17.23% (149 of 865)

o OH: 50.00% (13 of 26)

o WI ’00

- ’09: Not detected from 1 system

• % systems w/ detects >1⁄2HRL =

o IL: 0.12% (1 of 865)

Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (2007)

• Detected in 2 CWSs; max detect in 1 CWS > HRL

CWSS (2006)

• % PWSs w/ detects = 4.26% (4 of 94); max detect = 203 μg/L, >HRL

EWG (2004

- 2009)

• 1 PWSs w/ max detect of >1⁄2HRL

Supplemental Ambient/Source Water Data

NAWQA Ambient Water (1992

- 2001)

• MRLs variable (most within 0.2 – 1 μg/L)

• No SW detects >HRL

• % GW samples w/ detects = 55.57% (1,807 of 3,252)

• % GW samples w/ detects >1⁄2HRL = 0.28% (9 of 3,252)

• % GW samples w/ detects >HRL = 0.15% (5 of 3,252)

• % SW samples w/ detects = 47.14% (1,120 of 2,376)

• % SW samples w/ detects >1⁄2HRL = 0.04% (1 of 2,376)

• % GW sites w/ detects = 56.51% (1,641 of 2,904)

• % GW sites w/ detects >1⁄2HRL = 0.31% (9 of 2,904)Phase 2 of Protocol for Regulatory Determination 3 April 2014

58 of 84 • % GW sites w/ detects >HRL = 0.17% (5 of 2,904)

• % SW sites w/ detects = 60.56% (238 of 393)

• % SW sites w/ detects >1⁄2HRL = 0.25% (1 of 393)

• Median detect = 3 μg/L

• 99%ile detect = 55.41 μg/L

• Max detect = 4,732.80 μg/L

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 32 states

• % GW samples w/ detects = 24.89% (388 of 1,559)

• % GW samples w/ detects >1⁄2HRL = 2.50% (39 of 1,559)

• % GW samples w/ detects >HRL = 2.37% (37 of 1,559)

• % SW samples w/ detects = 45.71% (18,231 of 39,884)

• % SW samples w/ detects >1⁄2HRL = 3.20% (1,276 of 39,884)

• % SW samples w/ detects >HRL = 2.85% (1,135 of 39,884)

• % GW sites w/ detects = 34.69% (170 of 490)

• % GW sites w/ detects >1⁄2HRL = 4.08% (20 of 490)

• % GW sites w/ detects >HRL = 3.67% (18 of 490)

• % SW sites w/ detects = 37.37% (3,854 of 10,313)

• % SW sites w/ detects >1⁄2HRL = 1.72% (177 of 10,313)

• % SW sites w/ detects >HRL = 1.09% (112 of 10,313)

• Median detect = 4 μg/L

• 90%ile detect = 44 μg/L

• Max detect = 75,000 μg/L
1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

NAWQA Quality of Public Supply Wells (1993

- 2007; Toccalino et al.)

• MRL = 0.06 - 1 μg/L

• No detects >1⁄2HRL or >HRL

• % samples w/ detects = 77.23% (485 of 628)

NAWQA Domestic Well Water Quality (1991

- 2004)

• 0.55% of wells exceeded 40 μg/L, but unknown if >HRLPhase 2 of Protocol for Regulatory Determination 3 April 2014

59 of 84 U.S. Glacial Aquifer Study (1991

- 2003)

• Max detect (304 μg/L) in 847 GW samples >HRL

Occurrence summary and/or other information:

• No detections >HRL in national data (NIRS)

• On UCMR 3

23. Nitrobenzene

• CASRN = 98953

• Substance Key = 3998

• A synthetic aromatic nitro compound that occurs as an oily, flammable liquid

• Commonly used in the production of aniline; as a solvent in the manufacture of paints, shoe polishes, floor polishes, metal polishes, explosives, aniline dyes, pesticides, and drugs (such as acetaminophen); and in its re

- distilled form (oil of mirbane), as an inexpensive perfume for soaps

Production / Release Data

TRI

- Release 20 10

• Surface water = 175 lbs/yr ( 2 states )

• Total = 321,721 lbs/yr ( 16 states)

TRI

- Release 200 8

• Surface water = 189 lbs/yr Critical Health Endpoint

• Increased methemoglobin (NTP, 1983)

• BMDL 10 = 1.8 mg/kg

- day

• UF = 1,000

• RfD = 0.002 mg/kg

- day

• Non

- cancer HRL = 14 μg/L

Health Assessment Status

• IRIS (2009)

• Likely to be carcinogenic to humans (2005 cancer guidelines) for all exposure routes (no cancer slope factor for oral route)

Sensitive Populations/Lifestages

• Neonates

• Persons prone to hereditary methemoglobinemia

• Persons with decreased glucose -6- phosphate dehydrogenase activity Analyzed using HRL of 14 μg/L

National Drinking Water Data UCMR 1 Finished Water Assessment Monitoring (2001

- 2003)

• MRL = 10 μg/L

• All detects (both detects) >HRL

• % samples w/ detects >HRL = 0.01% (2 of 33,576)

• % PWSs w/ detects >HRL = 0.05% (2 of 3,861)

• Median detect = 60.8 μg/L

• 99%ile detect = 100 μg/L

• Max de tect = 100 μg/L

UCMR 1 Finished Water Screening Survey (2001

- 2003)

• MRL = 0.5 μg/L

• Not detected in 2,306 samples from 295 PWSs

Non -N ational Drinking Water Data

State Drinking Water Data (1995

- 2007)

• No detects >1⁄2HRL or >HRL

• % systems w/ detects =

o CA: 0.18% (1 of 546)

o IL: Not detected from 85 systems

o OH: Not detected from 1,134 systems

Supplemental Drinking Water Data Referred to CVOC for evaluation. After evaluation of group information, EPA will decide whether to include in CVOC group and evaluate for regulatory determination.Phase 2 of Protocol for Regulatory Determination 3 April 2014

60 of 84 ( 2 states )

• Total = 487,627 lbs/yr ( 14 states)

TRI

- Release 2006

• Surface water = 42 lbs/yr (2 states)

• Total = 579,017 (15 states)

TRI

- Release 2004

• Surface water = 60 lbs/yr (1 state)

• Total = 350,303 (14 states)

CUSIUR Production Data

• >1B lbs/yr (1998, 2002)

• ≥ 1B lbs/yr (2006)

Fate / Transport

• Expected to be moderately to highly mobile in water, based on physical and chemical properties

• Not persistent in the environment (biodegrades fast with acclimation ) ( CCL CIS ) Recent CCRs from 26 CWSs that serve >1M (2002

- 2007)

• Not detected in 3 CWSs

EWG (2004

- 2009)

• 3 PWSs from 2 states w/ detects; no max detects >1⁄2HRL or >HRL

Supplemental Ambient/Source Water Data

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 1 8 states

• No SW detects >1⁄2HRL or >HRL

• % GW samples w/ detects = 30.41 % ( 350 of 1,151 )

• % GW samples w/ detects >1⁄2HRL = 2.17 % (25 of 1,151 )

• % GW samples w/ detects >HRL = 0. 09 % (1 of 1,151 )

• % SW samples w/ detects = 14.57 % ( 95 of 652 )

• % GW sites w/ detects = 40.82 % (24 0 of 588 )

• % GW sites w/ detects >1⁄2HRL = 3.91 % (23 of 588 )

• % GW sites w/ detects >HRL = 0. 17 % (1 of 588 )

• % SW sites w/ detects = 24.03 % ( 62 of 258 )

• Median detect = 0 μg/L

• 90%ile detect = 0.24 μg/L

• Max detect = 20 μg/L
1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

CDC Fourth National Report (2003

- 2004)

• 95%iles <LOD in 1,066 blood samples

Occurrence summary and/or other information:

• Few detections >HRL in national data (UCMR1)

• No detections >HRL in state drinking water data and one >HRL in ambient water dataPhase 2 of Protocol for Regulatory Determination 3 April 2014

61 of 84 24. N

- Nitrosodiethylamine (NDEA)

• CASRN = 55185

• Substance Key = 2243

• A nitrosamine

• A suspected disinfection by

product

• Used as an additive in gasoline and lubricants, and as an antioxidant and a stabilizer in plastics

Production / Release Data

TRI

- Release 20 10

• Surface water = 0 lbs/yr ( 0 states )

• Total = 633 lbs/yr (1 state )

TRI

- Release 200 8

• Surface water = 0 lbs/yr ( 0 states )

• Total = 650 lbs/yr (1 state )

TRI

- Release 2006

• Surface water = 0 lbs/yr (0 states)

• Total = 500 lbs/yr (1 state)

TRI

- Release 2004

• Surface water = 0 lbs/yr (0 states)

• Total = 1,000 lbs/yr (1 state)

Fate / Transport Critical Health Endpoint

• Cancer (liver and esophagus ) (Peto et al., 1991 a,b)

• CSF = 30 (mg/kg

- day) -1

• Cancer HRL = 0.0004 μg/L (includes ADAFs and exposure factors)

Health Assessment Status



### • Updated since CCL3

o Draft OW H ealth Advisory (201 1) [finalized in 2013]

Sensitive Populations/Lifestages

• Fetuses/infants/children

• Consumers of alcoholic beverages Analyzed using HRL of 0.0004 μg/L

National Drinking Water Data

UCMR 2 Finished Water Screening Survey (2008

- 2010)

• MRL = 0.005 μg/L

• All detects >HRL

• % samples w/ detects >HRL = 0.26% (46 of 18,038)

• %PWS w/ detects >HRL = 2.17% (26 of 1,198)

• Median detect = 0.007 μg/L

• 99%ile detect = 0.093 μg/L

• Max detect = 0.1 μg/L

Non -N ational Drinking Water Data

State Drinking Water Data (2001

- 2007)

• All detects >HRL

• % systems w/ detects >HRL =

o CA: 7.14% (1 of 14)

Supplemental Ambient/Source Water Data

STORET (SW Only)

• MRL unavailable (min detect = ND)

• No SW detect s in 3 samples from 3 sites in 3 states

Occurrence summary and/or other information:

• 2% of PWSs with detections in national data (UCMR2)

• Uncertainty in UCMR2 data; detection limit is 13 times higher than HRL; possible occurrence >HRL that is undetected

• One detection (>HRL) in CA drinking water data

• Included with NDMA in nitrosamine group Proceeds to phase 3

Rationale: The contaminant is of potential public health concern, does not have critical health or occurrence data gaps, and is part of the nitrosamine group

Health: Available health assessment

Occurrence: Occurrence at levels of public health concern in national and non

- national finished water dataPhase 2 of Protocol for Regulatory Determination 3 April 2014

62 of 84 • High mobility in soil (HSDB)

• High volatility in water; subject to photodegradation (HSDB)

25. N

- nitrosodimethylamine (NDMA)

• CASRN = 62759

• Substance Key = 2446

• A nitrosamine and is a disinfection by

- product

• Used as an industrial solvent, an anti

- oxidant, and, formerly, in the production of rocket fuel

Production / Release Data

TRI

- Release 2006

• Total = 0 lbs/yr (0 states)

TRI

- Release 1998

- 1999

• Air emissions = 134 lbs (2 states)

Fate / Transport

• Expected to be moderately mobile to very mobile in water, based on physical and chemical properties

• Subject to volatilization, photodegradation, and microbial degradation Critical Health Endpoint

• Cancer (liver) (Peto et al., 1991 a,b)

• CSF = 21 (mg/kg

- day) -1

• Cancer HRL = 0.0006 μg/L (includes ADAFs and exposure factors)

Health Assessment Status

• Updated since CCL3

o Draft OW H ealth Advis ory (201 1) [finalized in 2013]

Sensitive Populations/Lifestages

• Fetuses/infants/children

• Consumers of alcoholic beverages Analyzed using HRL of 0.0006 μg/L

National Drinking Water Data

UCMR 2 Finished Water Screening Survey (2008

- 2010)

• MRL = 0.002 μg/L

• All detects >HRL

• % samples w/ detects >HRL = 10.21% (1,841 of 18,040)

• % PWSs w/ detects >HRL = 27.05% (324 of 1,198)

• Median detect = 0.004 μg/L

• 99%ile detect = 0.06 μg/L

• Max detect = 0.63 μg/L

Non -N ational Drinking Water Data

State Drinking Water Data (2001

- 2007)

• All detects >HRL

• % systems w/ detects >HRL =

o CA: 23.76% (24 of 101)

Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (2006

- 2007)

• Detected in 1 CWS

• Avg. annual detects = 0.0008 μg/L (2006) and 0.0014 μg/L (2007)

>HRL

CWSS (2006) Proceeds to phase 3

Rationale: The contaminant is of potential public health concern, does not have critical health or occurrence data gaps, and is part of the nitrosamine group

Health: Available health assessment

Occurrence: Significant occurrence at levels of public health concern in national and

non

- national finished water dataPhase 2 of Protocol for Regulatory Determination 3 April 2014

63 of 84 (ATSDR) • % samples w/ detects = 22% (2 of 9); detects = 0.0014 μg/L, >HRL

EWG (2004

- 2009)

• 26 PWSs from 3 states w/ detects >HRL; all detects >HRL

Supplemental Ambient/Source Water Data

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 14 states

• No GW detects >1⁄2HRL or >HRL

• % GW samples w/ detects = 32.44 % ( 133 of 410 )



### • % SW samples w/ detects = 13.55 % ( 68 of 502 )

• % SW samples w/ detects >1⁄2HRL = 1.39% (7 of 502)



### • % SW samples w/ detects >HRL = 1.39% (7 of 502)

• % GW sites w/ detects = 40. 26 % ( 122 of 303 )



### • % SW sites w/ detects = 24. 71 % ( 4 2 of 170 )



### • % SW sites w/ detects >1⁄2HRL = 2.35% (4 of 170)



### • % SW sites w/ detects >HRL = 2.35% (4 of 170)



### • Median detect = 0 μg/L



### • 90%ile detect = 0 μg/L

• Max detect = 0.05 μg/L
1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

USGS VOCs in Highway Runoff

• Not detected

AwwaRF (early 2000s)

• % PWS w/ detects = 85.71% (18 of 21); median detect < 0.001 μg/L

Occurrence summary and/or other information:

• Significant occurrence >HRL; 27% of PWSs >HRL

• Uncertainty in national data (UCMR2); all detections are 3 times higher than HRL due to detection limit; likely more occurrencePhase 2 of Protocol for Regulatory Determination 3 April 2014

64 of 84 >HRL that is undetected

• 24% of PWSs had detections >HRL in CA finished water data

• Supplemental drinking water and ambient water data also demonstrate detections >HRL

• Included with other nitrosamines as a contaminant group

26. N

- Nitrosodi

- n - propylamine (NDPA)

• CASRN = 621647

• Substance Key = 8798

• A nitrosamine

• A disinfection byproduct

Production / Release Data

TRI

- Release 20 10

• Surface water = 0 lbs/yr ( 0 states )

• Total = 382 lbs/yr ( 2 states)

TRI

- Release 200 8

• Surface water = 0 lbs/yr ( 0 states )

• Total = 423 lbs/yr ( 2 states)

TRI

- Release 2006

• Surface water = 0 lbs/yr (0 states)

• Total = 751 lbs/yr (2 states)

TRI

- Release 2004

• Surface water = 0 lbs/yr (0 states)

• Total = 506 lbs/yr (2 states) Critical Health Endpoint

• Cancer (liver and esophagus ) (Druckrey et al., 1967 )

• CSF = 2 (mg/kg

- day) -1

• Cancer HRL = 0.007 μg/L (includes ADAFs and exposure factors)

Health Assessment Stat us

• Updated since CCL3

o Draft OW H ealth Advisory (201 1) [finalized in 2013]

Sensitive Populations/Lifestages

• Fetuses/infants/children

• Consumers of alcoholic beverages Analyzed using HRL of 0.007 μg/L

National Drinking Water Data

UCMR 2 Finished Water Screening Survey (2008

- 2010)

• MRL = 0.007 μg/L

• Not detected in 18,049 samples from 1,198 systems

Non -N ational Drinking Water Data

State Drinking Water Data (1995

- 2007)

• CA: Not detected in 55 systems

• IL: Not detected in 1 system

Supplemental Drinking Water Data

EWG (2004

- 2009)

• 1 PWS in 1 state w/ detects >HRL

Supplemental Ambient/Source Water Data

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 20 states

• % GW samples w/ detects = 32.62 % ( 349 of 1,070 )

• % G W samples w/ detects >1⁄2HRL = 1. 40 % ( 15 of 1,070) Proceeds to phase 3

Rationale: The contaminant is part of the nitrosamine group and does not have critical health or occurrence data gaps

Health: Available health assessment

Occurrence: No detections in national and non

national finished water dataPhase 2 of Protocol for Regulatory Determination 3 April 2014

65 of 84 Fate / Transport

• Moderate mobility in soil (HSDB)

• Low/moderate volatility in water; subject to photodegradation (HSDB) • % GW samples w/ detects >HRL = 1.40% (15 of 1,070)

• % SW samples w/ detects = 11.79 % ( 71 of 602 )

• % S W samples w/ detects >1⁄2HRL = 1.66 % ( 10 of 602 )

• % SW samples w/ detects >HRL = 1.66% (10 of 602)

• % GW sites w/ detects = 45.61 % ( 239 of 524 )

• % G W sites w/ detects >1⁄2HRL = 2. 48 % ( 13 of 524)

• % GW sites w/ detects >HRL = 2.48% (13 of 524)

• % SW sites w/ detects = 21.17 % ( 47 of 222 )

• % SW sites w/ detects >1⁄2HRL = 4.05 % ( 9 of 222 )

• % SW sites w/ detects >HRL = 4.05% (9 of 222)

• Median detect = 0 μg/L

• 90%ile detect = 0 μg/L

• Max detect = 20 μg/L
1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

Occurrence summary and/or other information:

• Not detected in national data (UCMR2); detection limit = HRL

• Not detected in CA drinking water data

• Included with NDMA in nitrosamine group

27. N

- Nitrosodiphenylamine (NDPhA)

• CASRN = 86306

• Substance Key = 3193

• A nitrosamine

• A possible disinfection byproduct

• A chemical reagent that is commonly used as rubber and polymer additive

Production / Release Data

TRI

- Release 20 10 Critical Health Endpoint

• Cancer (bladder) (NCI 1979)

• CSF = 0.0049 (mg/kg

- day) -1

• Cancer HRL = 7 μg/L

Health Assessment Status

• IRIS (198 7)

• P robable human carcinogen, group B2 (1986 cancer guidelines)

Sensitive Populations/Lifestages

• Fetuses/infants/children

• Consumers of alcoholic beverages

• Individuals with bladder dysfunction Analyzed using HRL of 7 μg/L

Non -N ational Drinking Water Data

State Drinking Water Data (1995

- 2007)

• CA: Not detected in 441 samples from 53 systems

Supplemental Ambient/Source Water Data

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 24 states

• % GW samples w/ detects = 31.56 % ( 355 of 1,125 ) Does not proceed to phase 3

Rationale: Even though it is part of the nitrosamine group, there is no EPA approved analytical method for monitoring.

Health: Health Assessment will be updated by Fall 2011

Occurrence: No detections in non

- national finished water data; no existing EPA approved drinking water analytical methodPhase 2 of Protocol for Regulatory Determination 3 April 2014

66 of 84 • Surface water = 0 lbs/yr ( 0 states )

• Total = 12 lbs/yr ( 1 state )

TRI

- Release 200 8

• Surface water = 0 lbs/yr ( 0 states )

• Total = 20 lbs/yr ( 1 state )

TRI

- Release 2006

• Surface water = 0 lbs/yr (0 states)

• Total = 14 lbs/yr (2 states)

TRI

- Release 2004

• Surface water = 0 lbs/yr (0 states)

• Total = 14 lbs/yr (2 states)

CUSIUR Production Data

• 10K

- 500K lbs/yr (2002)

Fate / Transport

• Low mobility in soil (HSDB)

• Moderate volatility in water; subject to photodegradation (HSDB) • % G W samples w/ detects >1⁄2HRL = 0.98 % ( 11 of 1,125 )

• % GW samples w/ detects >HRL = 0.98% (11 of 1,125)

• % SW samples w/ detects = 21.02 % ( 378 of 1,798 )

• % S W samples w/ detects >1⁄2HRL = 0.17 % ( 3 of 1,798 )

• % SW samples w/ detects >HRL = 0.17% (3 of 1,798)

• % GW sites w/ detects = 45.19 % ( 244 of 540 )

• % G W sites w/ detects >1⁄2HRL = 2. 04 % ( 11 of 5 40 )

• % GW sites w/ detects >HRL = 2.04% (11 of 540)

• % SW sites w/ detects = 31.49 % ( 177 of 562 )

• % SW sites w/ detects >1⁄2HRL = 0.53 % ( 3 of 562 )

• % SW sites w/ detects >HRL = 0.53% (3 of 562)

• Median detect = 0 μg/L

• 90%ile detect = 0.04 μg/L

• Max detect = 480 μg/L
1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

Occurrence summary and/or other information:

• Limited drinking water data

• Even though part of the nitrosamine group, there is no EPA approved analytical method for monitoring.

28. N

- nitrosopyrrolidine (NPYR)

• CASRN = 930552

• Substance Key = 10160

• A nitrosamine

• Used as a research chemical

• Suspected drinking water Criti cal Health Endpoint

• Cancer (liver) ( Peto et al., 1984; Gray et al., 1991 )

• CSF = 7 (mg/kg

- day) -1

• Cancer HRL = 0.00 2 μg/L (includes ADAFs and exposure factors) Analyzed using HRL of 0.00 2 μg/L

National Drinking Water Data

UCMR 2 Finished Water Screening Survey (2008

- 2010)

• MRL = 0.002 μg/L Proceeds to phase 3

Rationale: The contaminant is part of the nitrosamine group and does not have critical health or occurrence data gapsPhase 2 of Protocol for Regulatory Determination 3 April 2014

67 of 84 by

- product

Production / Release Data No data for production and release

Fate / Transport

• High mobility in soil (HSDB)

• Low volatility in water; subject to photodegradation (HSDB) Health Assessment Status

• Updated since CCL3

o Draft OW H ealth Advisory (201 1) [finalized in 2013]

Sensitive Populations/Lifestages

• Fetuses/infants/children Consumers of alcoholic beverages • % samples w/ detects = 0.23% (41 of 18,043)

• % samples w/ detects >1⁄2HRL = 0.13% (23 of 18,043)

• % samples w/ detects >HRL = 0.03% (5 of 18,043)

• % PWSs w/ detects = 1.75% (21 of 1,198)

• % PWSs w/ detects >1⁄2HRL = 1.34% (16 of 1,198)

• % PWSs w/ detects >HRL = 0.25% (3 of 1,198)

• Median detect = 0.004 μg/L

• 99%ile detect = 0.021 μg/L

• Max detect = 0.024 μg/L

Non -N ational Drinking Water Data

State Drinking Water Data (2006

- 2007)

• CA: Not detected in 4 systems

Supplemental Drinking Water Data

EWG (2004

- 2009)

• 4 PWSs in 2 states w/ detects; one detect >HRL

Supplemental Ambient/Source Water Data

STORET (SW Only)

• MRL unavailable (min detect = ND)

• No SW detect s in 7 samples from 6 sites in 3 states

Occurrence summary and/or other information:

• Some PWSs with detections, few (3) >HRL in national data (UCMR2)

• Not detected in CA drinking water data

• Some detections, one >HRL in other supplementary data

• Included with NDMA in nitrosamine group Health: Available health assessment

Occurrence: Few detections in national finished water data and one >HRL in supplementary dataPhase 2 of Protocol for Regulatory Determination 3 April 2014

68 of 84 29. Perfluorooctane sulfonic acid (PFOS)

• CASRN = 1763231

• Substance Key = 12176

• A perfluorooctylsulfonic and

heptadecafluoro -1- octanesulfonic acid

• Formerly used as a

surfactant or emulsifier in fire- fighting foam, circuit board etching acids, alkaline cleaners, and floor polish, and as a pesticide active ingredient for insect bait traps

Production / Release Data

CUSIUR Production Data

• 10K

- 500K lbs/yr (2002)

Fate / Transport

• Physical and chemical properties give contrary indications about expected mobility in water

• Persistent in the environment (biodegrades sometimes/recalcitrant ); BST is the highest category available to be awarded to a recalcitrant contaminant ( CCL CIS ) Critical Health Endpoint

• Thyroid effects (increase in TSH; decrease in T3); decrease in HDL (Seacat et al., 2002)

• NOAEL = 0.03 mg/kg

- day

• UF = 30

• Non

- cancer HRL = 0.2 μg/L

Health Assessment Status

• Provisional HA (2009)

• OW Health Advisory in process

Sensitive Populations/Lifestages

• Not completely characterized Analyzed using HRL of 0.2 μg/L

Supplemental Drinking Water Data

NJDEP (2006)

• MRL = 0.004 μg/L

• % sites w/ detects = 57% (13 of 23); max detect = 0.019 μg/L, no detects > 1⁄2HRL or >HRL

Select Minnesota Municipal Wells (ca. 2004)

• % PWSs w/ detects = 16.2% (6 of 37)

• Range of detects = ND

- 1.4 μg/L; max detect >HRL

Select Minnesota Non

- Community Wells (ca. 2004)

• Not detected in 22 PWSs

Select Minnesota Private Wells (ca. 2004)

• Not detected in 26 PWSs

Aggregate of Above Minnesota Wells (ca. 2004)

• % PWSs w/ detects = 7.1% (6 of 85); max detect = 1.4 μg/L, >HRL

Supplemental Ambient/Source Water Data

Tennessee River, AL (2000)

• MRL = 0.010 - 0.025 μg/L

• % samples w/ detects = 100% (40 of 40)

• Range of detects = <0.0168

- 0.144 μg/L; detects >1⁄2HRL

Lake Erie and Lake Ontario (200 3)

• MRL = 0.0007 μg/L

• % samples w/ detects = 100% (16 of 16)

• Range of detects = 0.011

- 0.121 μg/L; detects >1⁄2HRL

Upper Mississippi River Basin (2008) Does not proceed to phase 3

Rationale: The contaminant has health and occurrence data gaps

Health: Health assessment will not be completed by Fall 2011

Occurrence: Limited non

- national finished water data availablePhase 2 of Protocol for Regulatory Determination 3 April 2014

69 of 84 • MRL = 0.001 μg/L

• % samples w/ detects = 97.1% (168 of 173); max detect = 0.287 μg/L, >HRL

CDC Fourth National Report (2003

- 2004)

• 95%ile concentration = 54.6 μg/L in 2,094 serum samples

Occurrence summary and/or other information:

• Detections >HRL in supplemental drinking water data, however limited studies available

• On UCMR 3

30. Perfluorooctanoic acid (PFOA)

• CASRN = 335671

• Substance Key = 6614

• A perfluorinated aliphatic carboxylic acid

• Used as an emulsifier and surfactant in fluoropolymers (such as Teflon), fire

fighting foams, cleaners, cosmetics, greases and lubricants, paints, polishes, adhesives, and photographic films

Production / Release Data

CUSIUR Production Data

• 10K

- 500K lbs/yr (1998, 2002)

• <500K lbs/yr (2006) Critical Health Endpoint

• Increase in maternal liver weight at term (Lau et al., 2006)

• BMDL 10 = 0.46 mg/kg

- day

• UF = 30

• Non

- cancer HRL = 0.4 μg/L

Health Assessment Status

• Provisional HA (2009)

• OW Health Advisory in process

Sensitive Populations/Lifestages

• Not com p letely characterized Analyzed using HRL of 0.4 μg/L

Supplemental Drinking Water Data

NJDEP (2006)

• MRL = 0.004 μg/L

• % PWSs w/ detects = 78% (18 of 23)

• Range of detects = <0.0045

- 0.039 μg/L, no detects > 1⁄2HRL or >HRL

Little Hocking, OH Water Distribution System (2006)

• Range of detects = 1.5

- 7.2 μg/L; detects >HRL

Little Hocking, OH Private Wells (2006)

• Range of detects = <0.01

- 14 μg/L; detects >HRL

Select Minnesota Municipal Wells (ca. 2004)

• % PWSs w/ detects = 16.2% (6 of 37)

• Range of detects = ND

- 0.9 μg/L; detects >HRL

Select Minnesota Non

- Community Wells (ca. 2004)

• Not detected in 22 PWSs

Select Minnesota Private Wells (ca. 2004) Does not proceed to phase 3

Rationale: The contaminant has a health and occurrence data gap

Health: Health assessment will not be completed by Fall 2011

Occurrence: Limited non

- national finished water data availablePhase 2 of Protocol for Regulatory Determination 3 April 2014

70 of 84 Fate / Transport

• Physical and chemical properties give contrary indications about expected mobility in water

• Persistent in the environment (biodegrades sometimes/recalcitrant ); BST is the highest category available to be awarded to a recalcitrant contaminant ( CCL CIS ) • % PWSs w/ detects = 3.8% (1 of 26)

• Range of detects = ND

- 0.67 μg/L; detects >HRL

Aggregate of Above Minnesota Wells (ca. 2004)

• % PWSs w/ detects = 8.2% (7 of 85)

• Range of detects = ND

- 0.9 μg/L; detects >HRL

Supplemental Ambient/Source Water Data

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 1 state

• % GW samples w/ detects = 82.05 % ( 1,586 of 1, 933 )

• % GW samples w/ detects >1⁄2HRL = 10.45 % ( 202 of 1,933)

• % GW samples w/ detects >HRL = 9.21 % ( 178 of 1,933)

• % SW samples w/ detects = 56.80 % ( 259 of 456 )

• % SW samples w/ detects >1⁄2HRL = 21.05 % ( 96 of 456)

• % SW samples w/ detects >HRL = 17.98 % ( 82 of 456)

• % GW sites w/ detects = 97.29 % ( 1,043 of 1,072 )

• % GW sites w/ detects >1⁄2HRL = 6.62 % ( 71 of 1,072)

• % GW sites w/ detects >HRL = 5.50 % ( 59 of 1,0 72)

• % SW sites w/ detects = 57.78 % ( 78 of 135 )

• % SW sites w/ detects >1⁄2HRL = 25.19 % (3 4 of 135)

• % SW sites w/ detects >HRL = 20.74 % ( 28 of 135)

• Median detect = 0 μg/L

• 90%ile detect = 1.796 μg/L

• Max detect = 48 ,50 0 μg/L
1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

Tennessee River, AL (2000)

• MRL = 0.025 μg/L

• % samples w/ detects = 45% (18 of 40)

• Range of detects = 0.14

- 0.598 μg/L; detects >HRLPhase 2 of Protocol for Regulatory Determination 3 April 2014

71 of 84 Lake Erie and Lake Ontario (2003)

• MRL = 0.013 μg/L

• % samples w/ detects = 100% (16 of 16)

• Range of detects = 0.015

- 0.070 μg/L, no detects > 1⁄2HRL or >HRL

Upper Mississippi River Basin (2008)

• MRL = 0.001 μg/L

• % samples w/ detects = 97.1% (168 of 173); max detect = 0.125 μg/L, no detects > 1⁄2HRL or >HRL

CDC Fourth National Report (2003

- 2004)

• 95%ile concentration = 9.80 μg/L in 2,094 serum samples

Occurrence summary and/or other information:

• Detections >HRL in supplemental drinking water data, however limited studies available

• On UCMR 3

Analyzed using HRL of 1.1 μg/L

Supplemental Drinking Water Data

NJDEP (2006)

• MRL = 0.004 μg/L

• % PWSs w/ detects = 78% (18 of 23)

• Range of detects = <0.0045

- 0.039 μg/L, No detects >1⁄2HRL or >HRL

Little Hocking, OH Water Distribution System (2006)

• Range of detects = 1.5

- 7.2 μg/L; detects >HRL

Little Hocking, OH Private Wells (2006)

• Range of detects = <0.01

- 14 μg/L; detects >HRL

Select Minnesota Municipal Wells (ca. 2004)Phase 2 of Protocol for Regulatory Determination 3 April 2014

72 of 84 • % PWSs w/ detects = 16.2% (6 of 37)

• Range of detects = ND

- 0.9 μg/L; No detects >HRL

Select Minnesota Non

- Community Wells (ca. 2004)

• Not detected in 22 PWSs

Select Minnesota Private Wells (ca. 2004)

• % PWSs w/ detects = 3.8% (1 of 26)

• Range of detects = ND

- 0.67 μg/L; No detects >HRL

Aggregate of Above Minnesota Wells (ca. 2004)

• % PWSs w/ detects = 8.2% (7 of 85)

• Range of detects = ND

- 0.9 μg/L; No detects >HRL

Supplemental Ambient/Source Water Data

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 1 state

• % GW samples w/ detects = 82.05 % ( 1,586 of 1, 933 )

• % GW samples w/ detects >1⁄2HRL = 8.85 % ( 171 of 1,933)

• % GW samples w/ detects >HRL = 7.45 % ( 144 of 1,933)

• % SW samples w/ detects = 56.80 % ( 259 of 456 )

• % SW samples w/ detects >1⁄2HRL = 15.79 % ( 72 of 456)

• % SW samples w/ detects >HRL = 1 4.04 % ( 64 of 456)

• % GW sites w/ detects = 97.29 % ( 1,043 of 1,072 )

• % GW sites w/ detects >1⁄2HRL = 5.22 % ( 56 of 1,072)

• % GW sites w/ detects >HRL = 4.10 % ( 44 of 1,072)

• % SW sites w/ detects = 57.78 % ( 78 of 135 )

• % SW sites w/ detects >1⁄2HRL = 20.74 % ( 28 of 135)

• % SW sites w/ detects >HRL = 18.52 % ( 25 of 135)

• Median detect = 0 μg/L

• 90%ile detect = 1.796 μg/L

• Max detect = 48 ,50 0 μg/L
1 A minimum value of zero may represent a detection that was enteredPhase 2 of Protocol for Regulatory Determination 3 April 2014

73 of 84 into the database as a non

- numerical value (e.g., “Present”)

Ten nessee River, AL (2000)

• MRL = 0.025 μg/L

• % samples w/ detects = 45% (18 of 40)

• Range of detects = <0.025

- 0.598 μg/L; No detects >HRL

Lake Erie and Lake Ontario (2003)

• MRL = 0.013 μg/L

• % samples w/ detects = 100% (16 of 16)

• Range of detects = 0.015

- 0.070 μ g/L, No detects >1⁄2HRL or >HRL

Upper Mississippi River Basin (2008)

• MRL = 0.001 μg/L

• % samples w/ detects = 97.1% (168 of 173); max detect = 0.125 μg/L, no detects > 1⁄2HRL or >HRL

CDC Fourth National Report (2003

- 2004)

• 95%ile concentration = 9.80 μg/L in 2,094 serum samples

Occurrence summary and/or other information:

• Detections >HRL in supplemental drinking water data, however limited studies available

• On UCMR 3

31. RDX (Hexahydro

- 1,3,5

- trinitro

- 1,3,5

- triazine)

• CASRN = 121824

• Substance Key = 5404

• A nitrated triazine

• An explosive

• Has been used as a rat poison

Production / Release Data Critical Health Endpoint

• Inflammation of the prostate (U.S. DOD, 1983)

• NOEL = 0.3 mg/kg

- day

• UF = 100

• RfD = 0.003 mg/kg

- day

• Non

- cancer HRL = 21 μg/L

Health Assessment Status

• IRIS (1988)

• On the 2012 IRIS Agenda

• Possible human carcinogen, group Analyzed using HRL of 21 μg/L

National Drinking Water Data UCMR 2 Finished Water Assessment Monitoring (2008

- 2010)

• MRL = 1 μg/L

• No detects >1⁄2HRL or >HRL

• % samples w/ detects = 0.01% (4 of 32,015)

• % PWSs w/ detects = 0.07% (3 of 4,137)

• Median detect = 1.065 μg/L

• 99%ile detect = 1.1 μg/L

• Max detect = 1.1 μg/L Does not p roceed to phase 3

Rationale: The contaminant has no or low potential of public health concern , but has a health data gap.

Health: Health assessment will not be updated by Fall 2011

Occurrence: Few detections in recent nationalPhase 2 of Protocol for Regulatory Determination 3 April 2014

74 of 84 CUSIUR Production Data

• >500K

- 1M lbs/yr (1998)

• >1M

- 10M lbs/yr (2002)

Fate / Transport

• Expected to be moderately to highly mobile in water, based on physical and chemical properties

• Not expected to be persistent in the environment (biodegrades fast with acclimation ) ( CCL CIS ) C (1986 cancer guidelines)

Sensitive Populations/Lifestages

• None identified Non -N ational Drinking Water Data

State Drinking Water Data (2006)

• CA: Not detected from 1 system

Supplemental Ambient/Source Water Data

STORET (SW only)

• MRL unavailable (min detect = ND )

• No SW detects in 31 samples from 11 sites in 1 state

Occurrence summary and/or other i nformation:

• Few detections in recent national data (UCMR 2); none >1⁄2 HRL

• Production increased from 1998 to 2002 finished water data

32. Strontium

• CASRN = 7440246

• Substance Key = 18848

• A naturally

- occurring element

• Commonly used as a faceplate glass additive, in pyrotechnics, in ferrite ceramic magnets, in master alloys, in pigments and fillers, and in electrolytic production of zinc

• Most applications use strontium carbonate as feedstock

Production / Release Data No data for production and Critical Health Endpoint

• Effects on bone structure (replacing calcium in bone) (Marie et al., 1985)

• BMDL 10 = 328 mg/kg

- day

• UF = 1,000

• RfD = 0.3 mg/kg

- day

• Period of sensitivity birth

- 18 yrs

• Non

- cancer HRL = 1, 500 μg/L (includes exposure factors for period of sensitivity )

Health Assessment Status

• Updated since CCL3

o Draft OW health assessment (201 1) [finalized 2013] Analyzed using HRL of 1, 500 μg/L

National Drinking Water Data

NIRS Finished Water [GW only] (1984

- 1986)

• MRL = 1 μg/L

• % PWSs w/ detects = 99.1% (980 of 989)

• % PWSs w/ detects >1⁄2HRL = 14.26 % ( 141 of 989)

• % PWSs w/ detects >HRL = 6.98 % ( 69 of 989)

• Median detect = 178 μg/L

• 99%ile detect = 7,339 μg/L

• Max detect = 43,550 μg/L

Non -N ational Drinking Water Data

State Drinking Water Data (1998

- 2005) Proceeds to phase 3

Rationale: The contaminant is of potential public health concern and does not have critical health or occurrence data gaps

Health: Available health assessment

Occurrence: Significant occurrence at levels of public health concern in national and

non

- national finished water dataPhase 2 of Protocol for Regulatory Determination 3 April 2014

75 of 84 release

Fate / Transport

• Expected to have low to moderate mobility in soils; mobility affected by salinity (ATSDR, HSDB)

• Strontium released to air as strontium oxide will react to from strontium hydroxide and strontium ions (ATSDR) Sensitive Populations/Lifestages

• Growing children (especially those with low dietary calcium and vitamin D)

• Adult s with kidney problems may be sensitive to impaired strontium excretion and retention

• Paget’s disease • % systems w/ detects =

o IL: 100% (19 of 19)

o OH: 93.75% (30 of 32)

o R9 Tribes: Not detected from 1 system

• % systems w/ detects >1⁄2HRL =

o IL: 26.32% (5 of 19)

o OH: 31.25% (10 of 32)

• % systems w/ detects >HRL =

o IL: 26.32% (5 of 19)

o OH: 21.88% (7 of 32)

Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (2007)

• Detected in 2 CWSs from 1 state (NY); no detects >1⁄2HRL or >HRL

CWSS (2006)

• Detected in 1 sample; no detects >1⁄2HRL or >HRL

EWG (2004

- 2009)

• At least 16 PWSs from 4 states w/ detects >HRL

Supplemental Ambient/Source Water Data

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 3 3 states

• % GW samples w/ detects = 93.92 % ( 2,179 of 2,320 )

• % GW samples w/ detects >1⁄2HRL = 23.92 % ( 555 of 2,320 )

• % GW samples w/ detects >HRL = 13.88 % ( 322 of 2,320 )

• % SW samples w/ detects = 96.74 % (39,780 of 41,121 )

• % SW samples w/ detects >1⁄2HRL = 21.56 % ( 8,866 of 41,121 )

• % SW samples w/ detects >HRL = 7.71 % ( 3,170 of 41,121 )

• % GW sites w/ detects = 9 7 .19% (865 of 890 )

• % GW sites w/ detects >1⁄2HRL = 23.37 % ( 208 of 890 )Phase 2 of Protocol for Regulatory Determination 3 April 2014

76 of 84 • % GW sites w/ detects >HRL = 13.48 % ( 120 of 890 )

• % SW sites w/ detects = 99.06 % ( 11,434 of 11,543 )

• % SW sites w/ detects >1⁄2HRL = 1 1 .55% (1, 333 of 11,543 )

• % SW sites w/ detects >HRL = 4 .6 2 % (5 33 of 11,543 )

• Median detect = 270 μg/L

• 90%ile detect = 1, 344.83 μg/L

• Max detect = 19,034,000 μg/L
1 A mini mum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

U.S. Glacial Aquifer Study (1991

- 2003)

• Max detect (9,120 μg/L) in 552 GW samples >HRL

NAWQA Carbonate Aquifer Study (1993

- 2005)

• Max detect (43,950 μg/L) >HRL

NAWQA Domestic Well Water Quality (1991

- 2004)

• 6.49% of wells exceeded 4,000 μg/L, >HRL

NAWQA Quality of Public Supply Wells (1993

- 2007; Toccalino et al.)

• MRL = 0.02 - 5 μg/L

• % samples w/ detects = 100.00% (503 of 503)

• % samples w/ detects >1⁄2HRL = 25. 05 % ( 126 of 503)

• % samples w/ detects >HRL = 12. 13 % ( 61 of 503)

USGS Report (1991

- 2006)

• 2.2 % of samples exceeded 4,000 μg/L

, >HRL

• Data from 446 wells in 16 states

Occurrence summary and/or other information:

• 7% of PWSs detections >HRL, 14 % >1⁄2 HRL in national ground water data (NIRS)

• High percentage of detects in non

- national drinking water data as well with a significant percentage >HRL and 1⁄2 HRL

• On UCMR 3Phase 2 of Protocol for Regulatory Determination 3 April 2014

77 of 84 33. Terbufos

• CASRN = 13071799

• Substance Key = 22585

• A phosphorodithioate pesticide

• Used as an insecticide

nematicide to control a variety of insect pests. It was first registered in 1974 to control insect pests on corn, sugar beets, and sorghum. Target pests include corn rootworms, wireworms, white grubs, billbugs, sugarbeet root maggots, cutworms, and nematodes

Production / Release Data

OPP Estimated Environmental Concentrations

• Surface water chronic = 1.3

- 5.5 μg/L

• Ground water chronic = 4.8

- 7.4 μg/L

NCFAP Total Pesticide Application 1997

• 6,515,603 lbs/yr (37 states)

Pesticide Industry Sales and Usage Report

• 1999: 5M

- 7M lbs

• 2001: 3M

- 5M lbs

RED 2006 Critical Health Endpoint

• Plasma ChE inhibition & reduced body/organs weights & male fertility

• NOAEL = 0.005 mg/kg

- day

• UF = 100

• RfD = 0.00005 mg/kg

- day

• Non

- cancer HRL = 0.35 μg/L

Health Assessment Status

• OPP RED (2006)

• Not classifiable as to human carcinogenicity, group D (1986 cancer guidelines)

Sensitive Populations/Lifestages

• None identified Analyzed using HRL of 0.35 μg/L

Non

- National Drinking Water Data

UCMR 1 Finished Water Screening Survey (2001

- 2003)

• MRL = 0.5 μg/L

• Not detected in 2,301 samples from 295 PWSs

State Drinking Water Data (2002

- 2007)

• CA: Not detected in 191 samples from 23 systems

Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (1997)

• Not detected in 1 CWS

PDP Raw and Finished Water (2001

- 2009 )

• Not detected in 4,168 samples

PMP Raw & Finished Water (1999)

• Not detected in any raw or finished samples

Supplemental Ambient/Source Water Data

NAWQA Ambient Water (1992

- 2001)

• MRLs variable (most are 0.013 μg/L)

• No GW detects >1⁄2HRL or >HRL

• % GW samples w/ detects = 0.03% (2 of 6,080)

• % SW samples w/ detects = 0.19% (28 of 14,480)

• % SW samples w/ detects >1⁄2HRL = 0.03% (4 of 14,480)

• % SW samples w/ detects >HRL = 0.01% (1 of 14,480)

• % GW sites w/ detects = 0.04% (2 of 5,211)

• % SW sites w/ detects = 1.05% (20 of 1,907) Proceeds to phase 3

Rationale: The contaminant has no or low occurrence at a level of public health concern, does not have critical health or occurrence data gaps and is included in a parent

degradate contaminant group

Health: Available health assessment

Occurrence: No detections in non

- national finished water dataPhase 2 of Protocol for Regulatory Determination 3 April 2014

78 of 84 • ~7.5M lbs of active ingredient used annually between 1987

- 1996

Fate / Transport

• Expected to be of low to moderate mobility in water, based on physical and chemical properties

• Moderately persistent in the environment (biodegrades slowly with acclimation ) ( CCL CIS ) • % SW sites w/ detects >1⁄2HRL = 0.21% (4 of 1, 907)

• % SW sites w/ detects >HRL = 0.05% (1 of 1,907)

• Median detect = 0.017 μg/L

• 99%ile detect = 0.56 μg/L

• Max detect = 0.56 μg/L

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 1 7 states

• No GW detects in 699 samples from 441 sites

• % SW samples w/ detects: 7.84 % ( 457 of 5, 826 )

• % SW samples w/ detects >1⁄2HRL = 0. 39 % ( 23 of 5,826 )

• % SW samples w/ detects >HRL = 0.0 3 % (2 of 5,826 )

• % SW sites w/ detects: 22.08 % (1 3 8 of 625 )

• % SW sites w/ detects >1⁄2HRL = 2.24 % ( 14 of 625 )

• % SW sites w/ detects >HRL = 0.3 2 % (2 of 625 )

• Median detect = 0 μg/L

• 90%ile detect = 0. 01 μg/L

• Max detect = 3.2 μg/L
1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

NAWQA National Synthesis (1992

- 2001)

• MRL = 0.009 μg/L

• GW: no max detects >1⁄2HRL or >HRL

• SW: max detect from agricultural sites (0.56 μg/L) >HRL

USGS CWSs Drawing from Streams and Groundwater (2002

- 2005)

• Not detected

NAWQA Carbonate Aquifer Study (1993

- 2005)

• Not detected in 1,027 samples

NAWQA Domestic Well Water Quality (1991

- 2004)

• % samples w/ detects = 0.04% (1 of 2,539); no detects >1⁄2HRL or >HRLPhase 2 of Protocol for Regulatory Determination 3 April 2014

79 of 84 NAWQA Quality of Public Supply Wells (1993

- 2007; Toccalino et al.)

• MRL = 0.006 - 0.013 μg/L

• Not detected in 898 samples

Terbufos REDs - EPA OPP

• 20 confirmed detections out of 4,563 GW samples taken in 13 states

• Range of detects = 0.01 - 20 μg/L

Occurrence summary and/or other information:

• Not detected in UCMR1 (SS), which is a statistically defined, national sample of 300 PWSs; some uncertainty because the minimum reporting limit is 1.5 times higher than the HRL

• No detections in CA drinking water data and a few detections in ambient water data with one >HRL and a few >1⁄2 HRL

• Included with Terbufos Sulfone (degradate) in contaminant group

34. Terbufos sulfone

• CASRN = 56070167

• Substance Key = 37071

• A degradate of terbufos

• See also parent compound

Production / Release Data Not produced commercially

Fate / Transport

• Expected to be moderately to highly mobile in water, based on physical and chemical properties.

• Moderately persistent in the environment (biodegrades Critical Health Endpoint

• Parent compound (Terbufos)

• Plasma ChE inhibition & reduced body/organs weights & male fertility

• NOAEL = 0.005 mg/kg

- day

• UF = 100

• RfD = 0.00005 mg/kg

- day

• Non

- cancer HRL = 0.35 μg/L

Health Assessment Status

• Parent compound [OPP RED (2006)]

• Parent compound [Not classifiable as to human carcinogenicity, group D (1986)]

Sensitive Populations/Lifestages

• None identified Analyzed using HRL of 0.35 μg/L

National Drinking Water Data

UCMR 2 Finished Water Assessment Monitoring (2008

- 2010)

• MRL = 0.4 μg/L

• All detects >HRL

• % samples w/ detects >HRL = 0.003% (1 of 32,012)

• % PWS w/ detects >HRL = 0.02% (1 of 4,138)

• Median detect = 0.42 μg/L

• 99%ile detect = 0.42 μg/L

• Max detect = 0.42 μg/L

Supplemental Drinking Water Data

PDP Raw and Finished Water (2001

- 2009 ) Proceeds to phase 3

Rationale: The contaminant has no or low occurrence at a level of public health concern, does not have critical health or occurrence data gaps, and is included in a parent

degradate contaminant group

Health: Available parent health assessment

Occurrence: No detections in national finished water data and supplemental drinking water and ambient water dataPhase 2 of Protocol for Regulatory Determination 3 April 2014

80 of 84 slowly with acclimation ) ( CCL CIS ) • Not detected in 4,101 samples

Supplemental Ambient/Source Water Data

Iowa Data

• Not detected in 13 wells

Occurrence summary and/or other information:

• Not detected in national data (UCMR2); minimal uncertainty because the detection limit is slightly higher than the HRL

• No detections in supplemental drinking water (Iowa) and ambient water data (PDP)

35. Vanadium

• CASRN = 7440622

• Substance Key = 18882

• A naturally

- occurring element

• Commonly used as Vanadium pentoxide which is a chemical intermediate and a catalyst

Production / Release Data

TRI

- Release 20 10 (vanadium compounds)

• Surface water = 451,251 lbs/yr (37 states )

• Total = 50,810,725 lbs/yr ( 48 states)

TRI

- Release 20 10 (vanadium except when contained in an alloy) Critical Health Endpoint (s)

• Minor renal effects (Domingo et al., 1985 in ATSDR 1992 )

o NOAEL = 0.3 mg/kg

- day

o UF = 100

o ATSDR MRL = 0.003 mg/kg

- day

o Non

- cancer HRL = 21 μg/L

• Blood pressure, body weight, and hematological effects (12 week human study) ( Fawcett et al. 1997 in Draft ATSDR 2009 )

o NOAEL = 0.12 mg/kg

- day

o UF = 10

o ATSDR MRL = 0.01 mg/kg

- day

o Non

- cancer HRL = 70 μg/L

Health Assessment Status

• ATSDR (1992)

• Updated since CCL3

o Draft ATSDR (2009) [became final in 2012]

• On the 2012 IRIS Agenda Analyzed using HRLs of 21 μg/L and 70 μg/L

Analysis at HRL of 21 μg/L:

National Drinking Water Data

NIRS Finished Water [GW only] (1984

- 1986)

• MRL = 3 μg/L

• % PWSs w/ detects = 14.76% (146 of 989)

• % PWSs w/ detects >1⁄2HRL =4.75% (47 of 989)

• % PWSs w/ detects >HRL = 1.72% (17 of 989)

• Median detect = 7.3 μg/L

• 99%ile detect = 45.1 μg/L

• Max detect = 70.4 μg/L

Non -N ational Drinking Water Data

State Drinking Water Data (1996

- 2007)

• % systems w/ detects =

o CA: 67.61% (1,824 of 2,698)

o IL: Not detected from 17 systems Does not proceed to phase 3

Rationale: The contaminant likely has no or low potential for public health concern, but has a health data gap.

Health: Non

- EPA h ealth assessment will not be updated by Fall 2011

Occurrence: No detections > draft HRL in national finished water data but some in non

national finished water and ambient water data at levels of potential public health concern based on the draft HRLPhase 2 of Protocol for Regulatory Determination 3 April 2014

81 of 84 • Surface water = 8,773 lbs/yr ( 6 states )

• Total = 2,341,137 lbs/yr ( 21 states)

TRI

- Release 200 8 (vanadium compounds)

• Surface water = 1,196,720 lbs/yr (39 states )

• Total = 42,805,369 lbs/yr ( 49 states)

TRI

- Release 200 8 (vanadium except when contained in an alloy)

• Surface water = 7 ,790 lbs/yr ( 5 states )

• Total = 2,264,849 lbs/yr ( 19 states)

TRI

- Release 2006 (vanadium compounds)

• Surface water = 402, 734 lbs/yr (38 states)

• Total = 50,462,858 lbs/yr (47 states)

TRI

- Release 2006 (vanadium except when contained in an alloy)

• Surface water = 16,889 lbs/yr (5 states)

• Total = 2,591,471 lbs/yr (21 states)

TRI

- Release 200 4 (vanadium compounds)

• Surface water = 662,878 Sensitive Populations/Lifestages

• Individuals with compromised renal systems o OH: Not detected from 23 systems

• % systems w/ detects >1⁄2HRL =

o CA: 35.73% (964 of 2,698)

• % systems w/ detects >HRL =

o CA: 17.90% (483 of 2,698)

Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (2007)

• Detected in 1 CWS; no detects >1⁄2HRL or >HRL in 1 CWS

CWSS (2006)

• % samples w/ detects = 80% (4 of 5); no detects >1⁄2HRL or >HRL

EWG (2004

- 2009)

• 670 PWSs from 4 states w/ detects; at least 10 of these PWSs (all in one state) had detects >HRL

Supplemental Ambient/Source Water Data

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 44 states

• % GW samples w/ detects = 49.83 % ( 2,069 of 4,152 )

• % GW samples w/ detects >1⁄2HRL = 11.49 % ( 477 of 4,152 )

• % GW samples w/ detects >HRL = 10.04 % ( 417 of 4,152 )

• % SW samples w/ detects = 49.21 % ( 39,501 of 80,264 )

• % SW samples w/ detects >1⁄2HRL = 7.57 % ( 6,073 of 80,264 )

• % SW samples w/ detects >HRL = 3.27 % ( 2,625 of 80,264 )

• % GW sites w/ detects = 75.27 % ( 691 of 918)

• % GW sites w/ detects >1⁄2HRL = 32.57 % ( 299 of 918 )

• % GW sites w/ detects >HRL = 29.41 % ( 270 of 918 )

• % SW sites w/ detects = 48.82 % ( 6,952 of 14,240 )

• % SW sites w/ detects >1⁄2HRL = 14.04 % (1, 999 of 14,240 )Phase 2 of Protocol for Regulatory Determination 3 April 2014

82 of 84 lbs/yr (3 7 states)

• Total = 52,583,423 lbs/yr (48 states)

TRI

- Release 200 4 (vanadium except when contained in an alloy)

• Surface water = 1,170 lbs/yr (6 states)

• Total = 1,600,795 lbs/yr (2 3 states)

Fate / Transport

• Commonly found as vanadyl ion (4+) or vanadate ion (5+) i n water; vanadate is more mobile

• Vanadyl and vanadate ions strongly bind to mineral and biogenic particulates in water; only 13% of vanadium in water is in solution (ATSDR, 2009) • % SW sites w/ detects >HRL = 7.11 % ( 1,012 of 14,240 )

• Median detect = 3. 2 μg/L

• 90%ile detect = 1 6 μg/L

• Max detect = 86,000 μg/L
1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

NAWQA Quality of Public Supply Wells (1993

- 2007; Toccalino et al.)

• MRL = 0.02 μg/L – 5 μg/L

• % samples w/ detects = 88.40% (404 of 457)

• % samples >1⁄2HRL = 21.66% (99 of 457)

• % samples w/ detects >HRL = 10.72% (49 of 457)

California GAMA Water Quality Monitoring (2002

- 2009)

• Detects >50 μg/L from 1.50% of wells (16 of 1,067), >HRL

U.S. Glacial Aquifer Study (1991

- 2003)

• % samples w/ detects = 62.3% (344 of 552)

• Max detect (294 μg/L) >HRL

Analysis at HRL of 70 μg/L:

National Drinking Water Data

NIRS Finished Water [GW only] (1984

- 1986)

• MRL = 3 μg/L

• No detects >HRL

• % PWSs w/ detects = 14.76% (146 of 989)

• % PWSs w/ detects >1⁄2HRL = 0.40% (4 of 989)

• Median detect = 7.3 μg/L

• 99%ile detect = 45.1 μg/L

• Max detect = 70.4 μg/L

Non

- N ational Drinking Water DataPhase 2 of Protocol for Regulatory Determination 3 April 2014

83 of 84 State Drinking Water Data (1996

- 2007)

• % systems w/ detects =

o CA: 67.61% (1,824 of 2,698)

o IL: Not detected from 17 systems

o OH: Not detected from 23 systems

• % systems w/ detects >1⁄2HRL =

o CA: 7.52% (203 of 2,698)

• % systems w/ detects >HRL =

o CA: 1.33% (36 of 2,698)

Supplemental Drinking Water Data

Recent CCRs from 26 CWSs that serve >1M (2007)

• Not detected >1⁄2HRL or >HRL in 1 CWS

CWSS (2006)

• % samples w/ detects = 80% (4 of 5); no detects >1⁄2HRL or >HRL

EWG (2004

- 2009)

• 670 PWSs from 4 states w/ detects; at least 4 of these PWSs had detects >HRL

Supplemental Ambient/Source Water Data

STORET

• MRL unavailable (min detect = 0 μg/L 1 )

• Data from 44 states

• % GW samples w/ detects = 49.83 % ( 2,069 of 4,152 )

• % GW samples w/ detects >1⁄2HRL = 9.06 % ( 376 of 4,152 )

• % GW samples w/ detects >HRL = 3.90 % (16 2 of 4,152 )

• % SW samples w/ detects = 49.21 % ( 39 ,5 01 of 80,264 )

• % SW samples w/ detects >1⁄2HRL = 2.07 % (1, 658 of 80

, 264 )

• % SW samples w/ detects >HRL = 1. 15 % ( 924 of 80,264 )

• % GW sites w/ detects = 75.27 % ( 691 of 918 )Phase 2 of Protocol for Regulatory Determination 3 April 2014

84 of 84 • % GW sites w/ detects >1⁄2HRL = 27.23 % ( 250 of 918 )

• % GW sites w/ detects >HRL = 15.25 % ( 1 40 of 9 18 )

• % SW sites w/ detects = 48.82 % ( 6, 952 of 14, 240 )

• % SW sites w/ detects >1⁄2HRL = 4.75 % ( 676 of 14,240 )

• % SW sites w/ detects >HRL = 2. 44 % ( 348 of 14,240 )

• Median detect = 3. 2 μg/L

• 90%ile detect = 16 μg/L

• Max detect = 86,000 μg/L
1 A minimum value of zero may represent a detection that was entered into the database as a non

- numerical value (e.g., “Present”)

NAWQA Quality of Public Supply Wells (1993

- 2007; Toccalino et al.)

• MRL = 0.02 μg/L – 5 μg/L

• % samples w/ detects = 88.40% (404 of 457)

• % samples >1⁄2HRL = 5.03% (23 of 457)

• % samples w/ detects >HRL = 0.44% (2 of 457)

California GAMA Water Quality Monitoring (2002

- 2009)

• Detects >50 μg/L from 1.50% of wells (16 of 1,067), >HRL

U.S. Glacial Aquifer Study (1991

- 2003)

• Max detect (294 μg/L) in 552 GW samples > HRL

Occurrence summary and/or other information:

• 4 detections >1⁄2 HRL but no detections >HRL in national data (NIRS)

• Some detections >HRL in non

- national drinking water data (CA) and ambient water data (STORET)

• On UCMR 3Appendix F - Summary of Phase 3 Reg Det Assessment for 1,2,3

- Trichloropropane

-- April 2014



# Summary of Phase 3 Regulatory Determination
Assessment for 1,2,3

- TrichloropropaneBackground • Volatile, chlorinated organic compound • Used as a chemical intermediate

, paint and varnish remover, solvent, and degreasing agent • No natural sources • Produc tion: 0.5 million

- 1 million lbs in 2002 (CUS)

- Down from > 10 million

- 50 million lbs in 1986 • Industrial releases to surface water: 187 lbs in 2008 (TRI)

- Down from 5,498 lbs in 2000 but up from 62 lbs reported in 1997 • Total industrial releases: 1,55 7 lbs in 2008 (TRI) 

## Evaluation of Statutory CriteriaHealth • IRIS Risk Assessment (200 9)

• Likely to be a carcinogenic to humans (2005 cancer guidelines ),

by a mutagenic mode of action • Critical Effect = Cancer

- Based on oral gavage multisite tumors st udy in mice (NTP, 1993)

- Cancer Slope factor = 30 (mg/kg

- day) -1

• HRL: 0.0004 μg/L (c ancer with ADAF )

• Non

- cancer effects = Increased ab solute liver weight

- Base d on 2

- year bioassay in male rats (NTP, 19 9 3)

- RfD = 0.00 4 mg/kg

- day; BMDL = 1.1 mg/kg

- day; UF = 300 Might the contaminant have an adverse effect on the healt h of persons? Yes Rationale: • Adverse effect s (from animal studies) are cancer (pharynx/palate, tongue, forestomach, liver, uterus, harderian gland) and increased liver weightOccurrence National Data :

• UCM Round 1 cross

- section , 1988

- 1992 (min detect = 0.1 μg/L):

- Detections in 44 of 17k systems (0. 25%)

- Detections in 76 of 57k samples (0.1 3 %)

- Likely underestimat ion of occurrence at levels of health

concern , since reporting levels exceeded HRL of 0.0004 μg/L by orders of magnitude • UCM Round 2 cross

- section , 1993

- 1997 (min detect = 0. 0 3 μg/L ; most common RL = 0.1 μg/L ):

- Detections in 19 of 24k systems (0. 08%)

- Detections in 23 of 98k samples (0.02%)

- Likely underestimat ion of occurrence at levels of health

concern , since repor ting levels exceeded HRL by orders of magnitude
Non

- National Data: • California, 1995

- 2007 (min detect = 0.001 μg/L)

- Detections in 157 of 3,939 systems (4 .0 %)

- Detections in 5k of 113k samples (4 .4 %) • Florida, 2004

- 2007 (min detect = 1.9 μg/L)

- Detection s in 1 of 27 systems ( 3.7 %)

- Detections in 1 of 1,766 samples (0.1%) Is the contaminant known to occur or is there a substantial likelihood that the contaminant will occur in PWSs with a frequency and at levels of public health concern? Yes Rationale:

• Detect ed under UCM Rounds 1 and 2

, with reporting levels orders of magnitude higher than the HRL of 0.0004 μg/L

. Recent monitoring suggests a continuing presence in waterAppendix F - Summary of Phase 3 Reg Det Assessment for 1,2,3

- Trichloropropane

-- April 2014



# Summary of Phase 3 Regulatory Determination
Assessment for 1,2,3

- Trichloropropane

• Illinois, 1998

- 2004 (min detect = 250 μg/L)

- Detections in 4 of 6 systems ( 6 7%)

- Detections in 4 of 11 samples ( 36 %)
• No rth Carolina, 1998

- 2005 (min detect = 0.57 μg/L)

- Detections in 5 of 2,493 systems (0.2%)

- Detections in 18 of 20k samples (0.09%) • Ohio, 1998

- 2005 (min detect = 0.5 μg/L)

- Detections in 1 of 2,532 systems (0.04%)

- Detections in 1 of 9,283 samples (0.01%) • Region 9 Tribes, 1998

- 2005 (min detect = 1.8 μg/L)

- Detection s in 2 of 279 systems (0.7%)

- Detections in 3 of 1,113 samples (0.3%) • South Dakota, 1990

- 2007 (min detect = 0.67 μg/L)

- Detections in 1 of 281 systems (0.4%)

- Detections in 1 of 1 ,110 samples (0.1%) • Texas, 1998

- 2005 (min detect = 13 μg/L)

- Detections i n 5 of 5,660 systems (0.1%)

- Detections in 7 of 36k samples (0.02%) • Wisconsin, 1983

- 199 9 (min detect = 0.1 μg/L)

- Detections in 1 1 of 1,8 26 systems (0. 6 %)

- Detections in 11 of 13 k samples (0.0 8 %) • Wisconsin, 2000

- 2009 (min detect = 3.9 μg/L)

- Detections in 1 of 1,123 systems (0. 1 %)

- Detections in 1 of 6,462 samples (0.0 2 %)Other Relevant Information • Some physical and chemical properties indicate mobilit y and volatility in water and soil

- Estimated half

- life in water is 38 days (PBT Profiler)

- Persistent in the environment (biodegrades slowly with acclimation)

• Estimated national p opulation exposed to 1,2,3

- trichloropropane at levels detected in UCM prog ram

- From UCM Round 1 cross

- section: 1 7.8 M ( 6. 65%)

- From UCM Round 2 cross

- section: 0. 2 M ( 0. 06 %)

- Likely underestimation of population served at levels of health

concern , since reporting levels exceeded HRL by orders of magnitude • Sensitive populations

- P regnant women /Fetuses/Infants/Children

- Individuals with liver or kidney problems • Proposed for UCMR 3 monitoringAppendix F - Summary of Phase 3 Reg Det Assessment for 1,2,3

- Trichloropropane

-- April 2014



# Summary of Phase 3 Regulatory Determination
Assessment for 1,2,3

- TrichloropropaneConclusion The data suggest that 1,2,3 -t richloropropane has adverse health effects (criterion 1) and occurs at levels and frequency of public health concern (criteri on 2). The available information will be presented to the Administrator for determination of whether a drinking water regulation would present a meaningful opportunity to protect public health (criterion 3). EPA intends to co nsider whether to regulate of 1,2,3

- trichloropropane as part of a group of carcinogenic volatile organic compounds (cVOCs).Appendix F - Summary of Phase 3 Reg Det Assessment for 1,3

- Dinitrobenzene

-- April 2014



# Summary of Phase 3 Regulatory Determination
Assessment for 1,3

- DinitrobenzeneBackground • A nitrated aromatic compound

• Used as an industrial chemical and in the production of other substances

• No natural sources

• > 10 million - 50 million lbs produced in 198 6 (only available year) (CUS)

• Total industrial releases: 19,858 lbs in 2008 (TRI)

• Industrial releases to surface water: 2 lbs in 2008 (TRI)

-D own from high of 816 lbs in 1997 

## Evaluation of Statutory CriteriaHealth • Update not needed (no additional inform ation)

- IRIS (1988) & ATSDR (1995) are consistent

- Not classifiable as to human carcinogenicity, group D (1986 cancer guidelines )

• Critical effect: increased spleen weight (Cody et al., 1981)

- Based on sub

- chronic drinking water study in rats

- RfD = 0.0001 mg/kg

- day; NOAEL = 0.4 mg/kg

- day; UF = 3000

• HRL: 0.7 μ g/L (non

- cancer) Might the contaminant have an adverse effect on the health of persons?
Yes Rationale: Adverse effect is increased spleen weight (from animal studies)Occurrence National Data

• UCMR 2 A ssessment M onitoring , 2008

- 2010 (MRL = 0 .8

μ g/L)

- No detections in 32,017 samples from 4, 137 systems

- Possible underestimation of occurre nce at levels of health concern since MRL slightly higher than HRL of 0.7
μ g/L Is the contaminant known to

occur or is there a substantial likelihood that the contaminant will occur in PWSs with a frequency and at levels of public health concern?
No Rationale: IN UCMR 2, no detections > MRL of 0.8 μ g/L, which is slightly higher than HRl of 0.7 μ g/L.Other Relevant Information • Expected to be moderately to highly mobile in water, based on physical and chemical properties

- Estimated half- life in water is 38 days (PBT profiler)
-M oderately persistent in the environment (biodegrades slowly with acclimation)

• Estimated nationa l population exposed to concentrations

= 0% for UCMR2 since no detects > HRL in 32,017 samples from 4,137 systems

• Sensitive P opulations/Lifestages:

-I ndividuals with a genetic predispo sition to blood disorders and/or iron disorders
-M ales having other sper m production complications could also have increased sensitivity • Proposed for UCMR 3 monitoringAppendix F - Summary of Phase 3 Reg Det Assessment for 1,3

- Dinitrobenzene

-- April 2014Conclusion The data suggest that 1,3

- dinitrobenzene has adverse health effects (criterion 1) but does not occur at levels and frequency of public health co ncern (criterion 2). The available information will be presented to the Administrator for determination of whether a drinking water regulation would present a meaningful opportunity to protect public health (criterion 3).Appendix F - Summary of Phase 3 Reg Det Assessment for Chlorate

-- April 2014



# Summary of Phase 3 Regulatory Determination Assessment for ChlorateBackground • Inorganic chemical : ClO 3 - (+5 oxidation state of chlorine atom) • Chlorate salts are used in pesticides

- Approximately 2.8 million lbs of sodium chlorate applied annually (OP P’s 2006 RED) • No production data available from IUR program or industrial release data available from TRI • Chlorate can form as a drinking water treatment by

- product:

- During liquid hypochlorite storage

- Disinfection with chlorine dioxide 

## Evaluation of Statutory CriteriaHealth • OPP Risk Assessment (2006) • Critical Effect: Increased t hyroid gland follicular cell hypertrophy and mineralization

- Based on chronic study in rats (NTP, 2004)

- RfD = 0.03 mg/kg

- day ; BMDL = 0.9 mg/kg

- day ; UF = 30

• HRL: 210 μg/L (non

- cancer)

• Not likely to cause cancer at doses below those that alter

thyroid hormone homeostasis Might the contaminant have an adverse effect on the health of persons? Yes Rationale: • Adverse effect (from animal studies) is thyroid gland folli cular cell hypertrophy and mineralizationOccurrence Non

- National Data :

• DBP ICR, July 1997

- Dec 1998 (min detect = 20 μg/L):

- Detections > HRL of 210 μg/L at 34 of 82 systems (41%) using hypochlorite and/ or chlorine dioxide

- Plant Influent (Source Wate r): d etection s > HRL in 4 of 749 samples (0.5%) at 4 of 106 systems ( 4 %)

- Finished Water at Hypochlorite Systems: d etection s > HRL in 42 of 298 samples (14%) at 22 of 59 systems (37%)

- Finished Water at Chlorine Dioxide Systems: d etection s > HRL in 88 of 384 samples (23%) at 15 of 29 systems (52%)

- Chlorate levels are not highly variable throughout distribution system when chlorine dioxide is used

• State of Califor nia 2001

- 2007 (min detect = 0.01 μg/L)

- Detection s > HRL in 10 of 45 systems (22%) Is the contaminant known to occur or is there a substantial likelihood that the contaminant will occur in PWSs with a frequency and at levels of public health concern? Yes Rationale:

• Detections > HRL of 210 μg/L in 41% of 82 systems using hypochlorite and/ or chlorine dioxide (DBP ICR)Appendix F - Summary of Phase 3 Reg Det Assessment for Chlorate

-- April 2014



# Summary of Phase 3 Regulatory Determination Assessment for ChlorateOther Relevant Information • Sensitive populations

- Individuals with blood conditions such as anemia or those with kidney disease

- I ndivi duals with genetic diseases such as hereditary methemoglobinemia and glucose

- 6

- phosphate dehydrogenase deficiency

- Individuals who may be unusually sensitive to oxidants • Population exposed to concentrations > HRL at DBP ICR participating systems : 11.8M (28.4% of the population served by hypochlorite and chlorine dioxide systems included in the study)

• Disinfection by

- product • EPA is reviewing recent surveys (AWWA, EPA

- CWSS) that show substantial increases in the number of systems using disinfection
pr actices associated with high levels of chlorate formation • Proposed for UCMR 3 monitoringConclusion The data suggest that chlorate has adverse health effects (criterion 1) and occurs at levels and frequency of public health concern (criterion 2). The a vailable information will be presented to the Administrator to determine whether a drinking water regulation would present a meaningful opportunity to protect public health (criterion 3).Appendix F - Summary of Phase 3 Reg Det Assessment for Dimethoate

-- April 2014



# Summary of Phase 3 Regulatory Determination
Assessment for DimethoateBackground • A n organophosphate pesticide

• Commonly used as an insecticide on field crops (e.g., wheat, alfalfa, corn, and cotton), orchard crops, vegetable crops, in f orestry, and fo r residential purposes • Usage estimated at 1.8 million lbs in 2008 (OPP)

- Up from 1986: > 500,000

– 1 million lbs production/importation (CUS) •Total industrial releases: 15,561 lbs in 2008 (TRI) • No natural sources 

## Evaluation of Statutory CriteriaHealth • OPP Risk Assessment (2007)

- Possible human carcinogen, group C (1986 cancer guidelines) •Critical effect: B rain cholinesterase inhibition

- Based on 2

- year chronic feeding study in rats

- Chronic oral RfD = 0.0022 mg/kg

- day ; BMDL = 0.22 mg/kg

- day; UF = 100 •HRL: 15.4 μg/L (non

- cancer) Might the contaminant have an adverse effect on the health of persons? Yes Rationale: • Adverse effect (from animal studies) is brain cholinesterase inhibition • Possible human carcinogenOccurrence National Data •UCMR 2 A ssessment M onitoring, 2008

- 2010 ( MRL = 0.7 μg/L)

- No detections > MRL or HRL of 15.4 μg/L in 32 ,013 samples from 4,138 systems

• USGS data, 2002

- 2005 (Hopple et al., 2009 and Kingsbury et al., 2008) (reporting level = 0.0061 μg/L)

- Phase 1: No detections in 221 GW sa mples; 2 (1.4%) detections in 146 SW samples at 9 systems (max estimated at 0.009 μg/L);

no detections > 1⁄2 HRL

- Phase 2: No detections in 48 raw & finished GW samples Is the contaminant known to occur or is there a substantial likelihood that the contamina nt will occur in PWSs with a frequency and at levels of public health concern? No Rationale: No detections in UCMR 2 at the HRL of 15.4 μg/L

.Other RelevantInformation • Sensitive P opulations /Lifestages: None identified • Estimated national population exposed to concentrations = 0% for UCMR2 since no detects > HRL in 32,013 samples from 4,138 systems • Physical/chemical properties indicate very mobile in water

• 36% partitions to water (modeled system of water, air, soil, and sediment) • Moderately persistent (biodegrades slowly with acclimation)Appendix F - Summary of Phase 3 Reg Det Assessment for Dimethoate

-- April 2014



# Summary of Phase 3 Regulatory Determination
Assessment for DimethoateConclusion The data suggest that dimethoate has adverse health effects (criterion 1) but does not occur at levels and frequency of public health concern (criterion 2). The available information will be presented to the Administrator to determine whether a drinking water regulation would present a meaningful opportunity to protect public health (criterion 3).Appendix F - Summary of Phase 3 Reg Det Assessment for NDEA

-- April 2014



# Summary of Phase 3 Regulatory Determination
Assessment for NDEABackground • Organic nitrosamine compound, also known as N

- nitrosodiethylamine

• Used as an additive in gasoline and in lubricants, as an antioxidant, and as a stabilizer in

plastics

• Found in dis charges of municipal wastewater

• Found in some food products (e.g., cured meats and fish, beer, smoked products)

• Can form in the body by nitrosation of dietary amines

• By

- product from water treatment, particularly disinfection with chloramines 

## Evaluation of Statutory CriteriaHealth • OW Health Assessment (2011) – External peer review in process

• Likely to be a carcinogen ic to humans (2005 cancer guidelines )

,

by a mutagenic mode of action

• Critical Effect: Cancer

- Based on liver and esophageal tumors ( Peto et a l. 1991 )

- Cancer s lope f actor: 30 ( mg/kg

- day ) -1

• HRL: 0. 0004 μ g/L (c ancer with ADAF s) Might the contaminant have an adverse effect on the health of persons?
Yes Rationale:
Cancer in multiple animals (monkeys, mice, rats, hamsters, guinea pigs, rabbits, dogs ) and multiple tumor types ( liver, kidney, lung, esophageal, nasal cavity, tracheal, bronchial and forestomach )Occurrence National Data

• U CMR 2 S creening Survey, 2008

- 2010 ( MRL = 0.005 μg/L) :

-Detections > MRL in 46 of 18,038 samples (0.26%) -Detections at 2 6 of 1,198 systems (2. 17%)

- Likely underestimat ion of occurrence at levels of health

concern , since MRL higher than HRL
Non

- National Data

• State of California, 2001

- 2007 (min detect = 0.03 μ g/L )

-D etection > HRL in 1 of 106 samples (1%)

- Detection > HR L at 1 of 14 systems (7%) Is the contaminant known to occur or is there a substantial likelihood that the contaminant will occur in PWSs with a frequency and at levels of public health concern?
Yes Rationale: Detected in 2.17% of
UCMR 2 systems at the
MRL of 0.005 μg/L

. Also consider as part of nitrosamine group. Since MRL is approximately 12 times higher than HRL of 0.0004
μ g/L, occurrence at a level of health concern is likely higher.Appendix F - Summary of Phase 3 Reg Det Assessment for NDEA

-- April 2014



# Summary of Phase 3 Regulatory Determination
Assessment for NDEAOther RelevantInformation • Sensitive P opulations /Lifestages:

- Newborns and infants

- Heavy c onsumers of alcohol

• Processing changes since the 1970’s have resulted in :

- Reduced nitrate and nitrite for curing meat and fish

- Addition of chemicals that inhibit nitrosamine formation

- Better temperature controls when drying high pr otein foods

• Levels of dietary nitrosamines have decreased

• Estimated national population exposed to NDEA concentrations

above the UCMR 2 MRL ( 0.005 μ g/L ): 12.9M (7.1%) . Population exposed to NDEA concentrations above the HRL is likely higher

.Conclusion T he data suggest that NDEA has adverse health effects (criterion 1) and occurs at levels and frequency of public health concern (criterion 2). The available information will be presented to the Administrator to determine whether a drinking water regulation would present a meaningful opportunity to protect public health (criterion 3). EPA also intends to consider whether appropriate to regulate ND EA as part of a nitrosamine group.Appendix F - Summary of Phase 3 Reg Det Assessment for NDMA

-- April 2014



# Summary of Phase 3 Regulatory Determination
Assessment for NDMABackground • Organic nitrosamine compound, also known as N- nitrosodimethylamine

• H as been used as an industrial solvent and in the production of liquid rocket fuel,

antioxidants, and softeners f or copolymers

• Unintended byproduct of manufacturing activities at facilities (e.g., tanneries, fish processing

plants, foundries, and pesticide, dye, rubber, and tire manufacturing plant s)

• Found in d ischarges of municipal wastewater

• Found in some food products (e.g., cured meats and fish, beer, smoked products)

• Can form in the body by nitrosation of dietary amines

• By

- product from water treatment, particularly disinfection with chloramines 

## Evaluation of Statutory CriteriaHealth • OW Health Assessment ( 2011 )

• Likely to be a carcinogen ic to humans (2005 cancer guidelines )

,

by a mutagenic mode of action

• Critical Effect: Cancer

- Based on l iver tumors ( Peto et al. 1991 )

- Cancer slope f actor: 21 ( mg/kg

- day ) -1

• HRL: 0.0006 μ g/L (cancer with ADAFs) Might the cont aminant have an adverse effect on the health of persons?
Yes Rationale:
Cancer in multiple animal s (rats, mice, hamsters, guinea pigs, rabbits) and multiple tumor types (l iver, lung, kidney, nasal cavity, and bile duct )Occurrence National Data

• U CMR 2 S creening Survey, 2008

- 2010 ( MRL = 0.002 μg/L) :

- Detections in 1, 841 of 18

, 040 samples (10.21%) -Detections at 324 of 1

, 19 8 systems (27.05%)

- Likely underestimation of occurrence at levels of health concern, since MRL is 3 times higher than HRL
Non

- National Data

• State of California, 2001

- 2007 (m in detect = 0.00 1 μ g/L)

-Detections in 1,531 of 4,532 samples (34%) -Detections at 24 of 101 systems (24%) Is the contaminant known to occur or is there a substantial likelihood that the contaminant will occur in PWSs with a frequency and at levels of pub lic health concern?
Yes Rationale: Detected in 27% of
UCMR 2 systems at the MRL of 0.002 μ g/L

. Also consider as part of nitrosamine group. Since MRL is approximately 3 times higher than HRL of 0.006
μ g/L, occurrence at a level of health concern is likely h igher.Appendix F - Summary of Phase 3 Reg Det Assessment for NDMA

-- April 2014



# Summary of Phase 3 Regulatory Determination
Assessment for NDMAOther Relevant Information • Sensitive P opulations /Lifestages:

- Newborns and infants

- Heavy consumers of alcohol

• Processing changes since the 1970’s have resulted in :

- Reduced nitrate and nitrite for curing meat and fish

- Addition of chemicals that inhibit nitrosamine formation

- Better temperature controls when drying high protein foods

• Levels of dietary nitrosamines have decreased

• NDMA is the predominant nitrosamine in drinking water

(approx imately 27 % of systems)

• NDMA detected approx imately 4 times more frequently in SW

than GW in UCMR 2

- 19% vs 6% in chlorinating SW/Mixed vs GW systems

- 81% vs 39% in chloraminating SW/Mixed vs GW systems

• Estimated national population exposed to NDMA

concentrations above the UCMR 2 MRL ( 0.002 μg/L ): 87 .9 M ( 41 .5 %)

. Population exposed to NDMA concentrations above the HRL is likely higher

• Generally higher detection rates and concentrations at

maximum residence time location in distribution systems than at entry pointConclusion The data suggest that NDMA has adverse health effects (criterion 1) and occurs at levels and frequency of public health concern (criterion 2). The available information will be presented to the Administrator to determine whether a drinking water regulation would present a meaningful opportunity to protect public health (criterion 3). EPA also intends to consider whether appropriate to regulate NDMA as part of a nitrosamine group.Appendix F - Summary of Phase 3 Reg Det Assessment for NDPA

-- April 2014



# Summary of Phase 3 Regulatory Determination
Assessment for NDPABackground • Organic nitrosamine compound, also known as N

- nitrosodipropylamine

• O ccur s as a contaminant in substituted dinitrotrifluralin herbicides

• Found in discharges of municipal wastewate r

• Can form in the body by nitrosation of dietary amines

• By

- product from water treatment, particularly disinfection with chloramines


## Evaluation of Statutory CriteriaHealth • OW Health Assessment (2011) – External peer review in process

• Likely to be a carci nogenic to humans (2005 cancer guidelines )

,

by a mutagenic mode of action

• Critical Effect: Cancer

- Based on liver tumors ( Druckrey et al. 1967 )

- Cancer s lope f actor: 2 ( mg/kg

- day ) -1

• HRL: 0.007 μ g/L (Cancer with ADAF s) Might the contaminant have an adverse effect on the health of persons?
Yes Rationale:
Cancer in multiple animals (rats, mice) and multiple tumor types ( liver, nasal cavity, esophagus , tongue, forestomach, and lung)Occurrence National Data

• U CMR 2 S creening Survey, 2008

- 2010 ( MRL = 0.007 μg/L) :

- No detections > MRL or HRL of 0.007 μ g/L in 1 8 ,0 49 samples from 1 ,198 systems

• STORET , ambient water records (min detect = 0.19 μg/L )

-Detections > HRL in 22 of 1

, 142 samples (1.9%)

- Detections > HRL at 20 of 426 s ites (4.7%)
Non

- National Data

• Stat e of California 1995

- 2007

- No detections in 439 samples f rom 55 systems

• State of Illinois, 2005

-N o detection in 1 sample from 1 system Is the contaminant known to occur or is there a substantial likelihood that the contaminant will occur in PWSs with a frequency and at levels of public health concern? While not detected at the HRL of 0.007 μ g/L in
UCMR 2 , c onsider as part of nitrosamine group

.Other RelevantInformation • Sensitive P opulations /Lifestages:

- Newborns and infants

- Heavy consumers of alcoh ol

• Estimated national population exposed to concentrations = 0%

for UCMR2 since no detects > HRL in 18,049 samples from 1,198 systems

• Processing changes since the 1970’s have resulted in :

- Reduced nitrate and nitrite for curing meat and fish

- Addition of chemicals that inhibit nitrosamine formation

- Better temperature controls when drying high protein foods

• Levels of dietary nitrosamines have decreasedAppendix F - Summary of Phase 3 Reg Det Assessment for NDPA

-- April 2014



# Summary of Phase 3 Regulatory Determination
Assessment for NDPAConclusion The data suggest that ND P A has adverse health effects (criterion 1). The available informatio n will be presented to the Administrator to determine whether a drinking water regulation would present a meaningful opportunity to protect public health (criterion 3). EPA also intends to consider whether appropriate to regulate ND P A as part of a nitrosam ine group.Appendix F - Summary of Phase 3 Reg Det Assessment for NPYR

-- April 2014



# Summary of Phase 3 Regulatory Determination
Assessment for NPYRBackground • Organic nitrosamine compound, also known as N

- nitrosopyrrolidine

• Has been found in tobacco smoke

, processed meats

, and spice premixes

, air samples from

rubber tire plants

, and effl uent water from chemical factories

• Found in discharges of municipal waste water

• Can form in the body by nitrosation of dietary amines

• By

- product from water treatment, particularly disinfection with chloramines 

## Evaluation of Statutory CriteriaHealth • OW Health Assessment (2011) – External peer review in process

• Likely to be a carcinogen ic to humans (2005 cancer guidelines )

,

by a mutagenic mode of action

• Critical Effect: Cancer

- Based on l iver tumors ( Preussman et al

., 1977 )

- Cancer slope f actor: 2 ( mg/kg

- day ) -1
- HRL: 0 .007 μ g/L (c ancer with ADAF s) Might the contaminant have an adverse effect on the health of persons?
Yes Rationale: Liver tumors in multiple animal s (rats, mice, hamsters)Occurrence National Data

• U CMR 2 S creening Survey, 2008

- 2010 ( M RL = 0.002 μg/L) :

-Detections > HRL of 0.007 μ g/L in 5 of 18,04 3 samples (0. 03%) -Detections > HRL at 3 of 1,198 systems ( 0.2 5%)
Non

- National Data (min detect= N/A)

• State of California, 2006

- 2007

- No detections in 57 samples f rom 4 systems Is the contamin ant known to occur or is there a substantial likelihood that the contaminant will occur in PWSs with a frequency and at levels of public health concern?
Yes Rationale: Detected in 0.25% of
UCMR 2 systems at the HRL of 0.007 μ g/L

. Also consider as part of nitrosamine group.Other RelevantInformation • Sensitive P opulations /Lifestages:

- Newborns and infants

- Heavy consumers of alcohol

- Males may be more sensitive than females

• Processing changes since the 1970’s have resulted in :

- Reduced nitrate and nitrite for curing meat and fish

- Addition of chemicals that inhibit nitrosamine formation

- Better temperature controls when drying high protein foods

• Levels of dietary nitrosamines have decreased

• Estimated national population exposed to NPYR concentrationsAppendix F - Summary of Phase 3 Reg Det Assessment for NPYR

-- April 2014



# Summary of Phase 3 Regulatory Determination
Assessment for NPYR

>HRL ( from UCMR 2) : 0. 95 M ( 0. 56%)Conclusion The data suggest that NPYR has adverse health effects (criterion 1) and occurs at levels and frequency of public health concern (criterion 2). The available information will be presented to the Administrator to dete rmine whether a drinking water regulation would present a meaningful opportunity to protect public health (criterion 3). EPA also intends to consider whether appropriate to regulate NPYR as part of a nitrosamine group.Appendix F - Summary of Phase 3 Reg Det Assessment for RDX

-- April 2014



# Summary of Phase 3 Regulatory Determination
Assessment for RDXBackground • Organic compound, IUPAC name 1,3,5 -t rinitroperhydro

- 1,3,5

- triazine • Used as an explosive by the U.S. military (superseded TNT as the primarily used explosive) and for some civili an uses • No natural sources • Production: 1 million

- <10 million lbs in 2006 (CUS) • Industrial Releases: No data (TRI) 

## Evaluation of Statutory CriteriaHealth • IRIS Risk Assessment (19 88 )

- IRIS updated assessment scheduled to be completed (2011)

- Possible human carcinogen, group C (1986 cancer guidelines ) • Critical Effect = I nflammation of the prostate

- Based on 2

- year rat feeding study (U.S. DOD, 1983)

- RfD = 0.003 mg/kg

- day; NO A EL = 0.3 mg/kg

- day; UF = 100

• HRL: 21 μg/L (non

- cancer) Might the contaminant have an adverse effect on the health of persons? Yes Rationale: • Adverse effect (from animal studies ) is inflammation of the prostateOccurrence National Data

• UCMR 2 Assessment Monitoring, 2008

- 2010 (MRL =
1 μg/L)

- No detections > HRL of 21 μg/L in 32,015 samples from 4,137 systems Non

- National Data • Cali fornia, 2006 (min detect = N/A)

- No detections in 1 sample at 1 system Is the contaminant known to occur or is there a substantial likelihood that the contaminant will occur in PWSs with a frequency and at levels of public health concern? No Rationale:

• No detections above HRL of 21 μg/LOther RelevantInformation • Sensitive P opulations /Lifestages: None identified • Estimated national population exposed to concentrations = 0% for UCMR2 since no detects > HRL in 32,015 samples from 4,137 systemsConclusion The data suggest that RDX has adverse health effects (criterion 1) but does not occur at levels and frequency of public health concern (criterion 2). The available information will be presented to the Administrator to determine whether a drinking water regulation would present a meaningful opportunity to protect public health (criterion 3).Appendix F - Summary of Phase 3 Reg Det Assessment for Strontium

-- April 2014



# Summary of Phase 3 Regulatory Determination
Assessment for StrontiumBackground • Inorganic chemical (element, atomic number 38 on periodic table)

• Occurs n aturally . Enters water through contact with and weathering of rocks and soils, from atmospheric de position, and from wastewater discharges • Used in fertilizers, pyrotechnics, previously used in cathode

- ray tube TVs; present in coal • 11 strontium

- containing compounds reported as produced/imported in 2006 (CUS)

- Strontium carbonate reported as produced/imported in the greatest quantity (10 million

- <50 million lbs) • Industrial releases: no TRI data 

## Evaluation of Statutory CriteriaHealth • OW Health Assessment (2011)

– External peer review in
process

- Not classifiable as to human carcinogenicity, gr oup D (1986 cancer guidelines )

• Critical Effect: decreased bone calcification

- Based on a 9

- week oral study in male weanling rats (Marie et al., 1985)

- RfD = 0. 3 mg/kg

- day ; BMDL = 328 mg/kg

- day ; UF = 1,0 00 • HRL: 1,463 μg/L (non

- cancer) ; period of sensitivity birth

- 18yrs Might the contaminant have an adverse effect on the health of persons? Yes Rationale: • Adverse effect (from animal studies) is decreased bone calcificationOccurrence National Data : • NIRS, 1984

- 1986 , ground water systems only, on e sample per system (MRL = 1 μg/L):

- Detections > HRL of 1,463 μg/L in 70 of 989 systems (7. 1 %)
Non

- National Data : • Illinois, 1998

- 2005 , both ground water and surface water systems (min detect = 71 μg/L):

- Detections > HRL of 1,463 μg/L in 5 of 19 systems (2 6 %)

, including 1 of 3 SW systems (33%)

- Detections > HRL of 1,463 μg/L in 5 of 21 samples ( 24 %)

, including 1 of 3 SW samples (33%) • Ohio, 2000

- 2005 , both ground water and surface water systems (min detect = 4 μg/L):

- Detections > HRL of 1,463 μg/L in 7 of 32 systems ( 22%)

, includ ing 2 of 4 SW systems (50%)

- Detections > HRL of 1,463 μg/L in 1 8 of 77 samples (2 3 %)

, including 8 of 20 SW samples (40%) • Region 9 Tribes, 2003, ground water system only (min detect = N/A):

- No detections in 1 sample/system
• USGS data: 1993

- 2007 (Toccalino et al., 2010) , ground water systems only, one sample per system (min detect = 5.61 μg/L)

- Detections > HRL of 1,463 μg/L in 62 of 503 systems (12%) Is the contaminant known to occur or is there a substantial likelihood that the contaminant will occur in PWSs with a frequency and at levels of public health concern? Yes Rationale:

• NIRS data indicate

occurrence at levels > HRL of 1,463 μg/L in 7.1% of ground water systems

• Also detected above HRL thresholds at surface water systems ( based on limited sampling from Illinois and Ohio monitoring programs)Appendix F - Summary of Phase 3 Reg Det Assessment for Strontium

-- April 2014



# Summary of Phase 3 Regulatory Determination
Assessment for StrontiumOther Relevant Information • Mining in U.S. ceased in 1959. Annual imports of strontium minerals and compounds have steadily declined since 2001 to less than 10,000 metric tons • Expected to have moderate or moderate

- to

- low mobility in soils (ATSDR, HSDB) • Ubiquitous at low levels in ground water ( detected in 99% of NIRS systems at MRL of 1 μg/L) • Sensitive P opulation s/Lifestages:

- Growing children (especially those with low dietary calcium and vitamin D)

- Adult with renal problems may be sensitive to impaired strontium excretion and retention

- Padget’s disease

• Estimated national p opulation exposed ( from NIRS) :

- E xposed to concentrations > HRL of 1,463 μg/L: 10.7M (10.8%) • Proposed for UCMR 3 monitoringConclusion The data suggest that strontium has adverse health effects (criterion 1) and occurs at levels and frequency of public health concern (criterion 2). The available information will be presented to the Administrator to determine whether a drinking water regulation would present a meaningful opportunity to protect public health (criterion 3).Appendix F - Summary of Phase 3 Reg Det Assessment for Terbufos

-- April 2014



# Summary of Phase 3 Regulatory Determination
Assessment for TerbufosBackground • Terbufos is an organophosphate compound

• U sed as a pesticide , primarily on corn and sugar beets

-A pprox. 7.5 million lbs used per year between 1987 and 1996 (OPP’s 2006 RED)

- 8. 7 million lbs applied in 37 states in 1992 and 6.5 million lbs applied in 37 states in 1997 (NCFAP)

• Industrial releases: No TRI data available

• No natural source 

## Evaluation of Statutory CriteriaHealth • OPP Risk Assessment (2006)

- Not classifiable as to h uman carcinogenicity, group D (1986 cancer guidelines )

• Critical effect: Plasma c holinesterase inhibition

-B ased on cholinesterase inhibition from 28

- day and 1

- year stud ies in dogs

- RfD = 0.00 0 05 mg/kg

- day; NOAEL = 0.005 mg/kg

- day; UF = 100

• HRL: 0 .35 μ g/L (non

- cancer) Might the contaminant have an adverse effect on the health of persons?
Yes Rationale: Plasma cholinesterase inhibition (from animal studies)Occurrence Non

- National Data

• UC M R 1 screening survey: 2001

- 2003 (MRL = 0 .5 μg/L):

- No detection s > MRL or HRL of 0.35 μ g/L in 2, 301 samples from 295 systems

• USGS data: 1993

- 2007 (Toccalino et al

., 2010) (MRL = 0.006

-

0.013 μg/L):

- No detections in 898 samples/systems

• USGS data: 2002

- 2005 (Hopple et al

. , 2009 & Kingsbury et al

. ,

2008) (min detect = N/ A):

- Phase 1: No detections in 367 samples in 230 systems

- Phase 2: No detections in 48 raw and 48 finished water samples

• California , 2002

- 2007 (min detect = N/A):

- No detections in 191 samples from 23 systems Is the contaminant known to occur or is ther e a substantial likelihood that the contaminant will occur in PWSs with a frequency and at levels of public health concern?
No Rationale: In UCMR 1, no detections > HRL of 0.35 μ g/L.Other RelevantInformation • Limited soil mobility (HSDB)

• Sensitive P opul ation s/Lifestages: N one identified

• Estimated national population exposed to concentrations = 0%

for UCMR1 since no detects > HRL in 2,301 samples from 295 systemsAppendix F - Summary of Phase 3 Reg Det Assessment for Terbufos

-- April 2014



# Summary of Phase 3 Regulatory Determination
Assessment for TerbufosConclusion The data suggest that terbufos has adverse health effects (criterion 1) but doe s not occur at levels and frequency of public health concern (criterion 2). The available information will be presented to the Administrator to determine whether a drinking water regulation would present a meaningful opportunity to protect public health (c riterion 3).Appendix F - Summary of Phase 3 Reg Det Assessment for Terbufos Sulfone

-- April 2014



# Summary of Phase 3 Regulatory Determination
Assessment for Terbufos SulfoneBackground • Terbufos s ulfone is a degradate of the pesticide t erbufos (an organophosphate compound)

• Terbufos is used primarily on corn and sugar beets

-A pprox. 7.5 million lbs used per year between 1987 and 1996 (OPP’s 2006 RED)

- 8.7 million lbs applied in 37 states in 1992 and 6.5 million lbs applied in 37 states in 1997 (NCFAP)

• Industrial releases: No TRI data available

• No natural source 

## Evaluation of Statutory CriteriaHealth • D ata on terbufos sulfone health effects are inadequate; therefore the health effects assessment is based on data for the parent compound, terbufos

• OPP Risk Assessment for terbufos (2006)

- Not classifiable as to human carcinogenicity, group D (1986
cancer gu idelines)

• Critical effect: Plasma c holinesterase inhibition

-B ased on cholinesterase inhibition from 28

- day and 1

- year stud ies in dogs

- RfD = 0.00005 mg/kg

- day; NOAEL = 0.005 mg/kg

- day; UF = 100

• HRL: 0.35 μ g/L (non

- cancer) Might the contaminant have an ad verse effect on the health of persons?
Yes Rationale: Plasma cholinesterase inhibition (from animal studies)Occurrence National Data

• UCMR 2 Assessment Monitoring
, 2008

- 2010 (MRL= 0.4 μ g/L) :

- Detection > HRL of 0.35 μ g/L in 1 of 4, 138 systems (0.02%)

- HRL is less than the MRL
Non

- National Data

• Iowa (min

- detect= N/A):

-N o detections in 13 wells Is the contaminant known to occur or is there a substantial likelihood that the contaminant will occur in PWSs with a frequency and at levels of public health co ncern?
No Rationale: In UCMR 2 survey, o nly a single detection > HRL of
0.35 μ g/L

.Other RelevantInformation • Expected to be more mobile in soil and more resistant to biodegradation than the parent compound, terbufos (OPP RED)

• Estimated national p opulat ion exposed to concentrations > HRL ( from UCMR 2 ): 44,600 (0. 02 %)

• Sensitive P opulations/Lifestages: N one identifiedAppendix F - Summary of Phase 3 Reg Det Assessment for Terbufos Sulfone

-- April 2014



# Summary of Phase 3 Regulatory Determination
Assessment for Terbufos SulfoneConclusion The data suggest that terbufos sulfone has adverse health effects (criterion 1) but does not occur at levels and frequency of public health concern (criterion 2). The available information will be presented to the Administrator to determine whether a drinking water regulation would present a meaningful opportunity to protect public health (criterion 3).