30610 Federal Register / Vol. 79, No. 102 / Wednesday, May 28, 2014 / Notices 

8 59 FR 36969 (July 20, 1994). 

209(b)(1)(C) (as EPA has interpreted that 

subsection in the context of section 

209(b) motor vehicle waivers).8

In order to be consistent with section 

209(a), California’s nonroad standards 

and enforcement procedures must not 

apply to new motor vehicles or new 

motor vehicle engines. To be consistent 

with section 209(e)(1), California’s 

nonroad standards and enforcement 

procedures must not attempt to regulate 

engine categories that are permanently 

preempted from state regulation. To 

determine consistency with section 

209(b)(1)(C), EPA typically reviews 

nonroad authorization requests under 

the same ‘‘consistency’’ criteria that are 

applied to motor vehicle waiver 

requests. Pursuant to section 

209(b)(1)(C), the Administrator shall not 

grant California a motor vehicle waiver 

if she finds that California ‘‘standards 

and accompanying enforcement 

procedures are not consistent with 

section 202(a)’’ of the Act. Previous 

decisions granting waivers and 

authorizations have noted that state 

standards and enforcement procedures 

are inconsistent with section 202(a) if: 

(1) There is inadequate lead time to 

permit the development of the necessary 

technology giving appropriate 

consideration to the cost of compliance 

within that time, or (2) the federal and 

state testing procedures impose 

inconsistent certification requirements. 

If California amends regulations that 

EPA has already authorized, California 

can seek EPA confirmation that the 

amendments are within the scope of the 

previous authorization. A within-thescope confirmation, without a full 

authorization review, is permissible if 

three conditions are met. First, the 

amended regulations must not 

undermine California’s determination 

that its standards, in the aggregate, are 

as protective of public health and 

welfare as applicable federal standards. 

Second, the amended regulations must 

not affect consistency with section 

202(a) of the Act. Third, the amended 

regulations must not raise any ‘‘new 

issues’’ affecting EPA’s prior 

authorizations. 

III. EPA’s Request for Comments 

As stated above, EPA is offering the 

opportunity for a public hearing, and is 

requesting written comment on issues 

relevant to a within-the-scope analysis 

pertaining to CARB’s amendments 

affecting compliance flexibility and 

reduced compliance costs. Specifically, 

we request comment on whether 

California’s CHE amendments: (1) 

Undermine California’s previous 

determination that its standards, in the 

aggregate, are at least as protective of 

public health and welfare as comparable 

federal standards; (2) affect the 

consistency of California’s requirements 

with section 209 of the Act; or (3) raise 

any other new issues affecting EPA’s 

previous waiver or authorization 

determinations. 

Should any party believe that the 

amendments noted above are not within 

the scope of the previous authorization, 

EPA also requests comment on whether 

the CARB CHE amendments meet the 

criteria for a full authorization. 

Specifically, we request comment on: (a) 

Whether CARB’s determination that its 

standards, in the aggregate, are at least 

as protective of public health and 

welfare as applicable federal standards 

is arbitrary and capricious, (b) whether 

California needs such standards to meet 

compelling and extraordinary 

conditions, and (c) whether California’s 

standards and accompanying 

enforcement procedures are consistent 

with section 209 of the Act. 

EPA also requests comment on 

whether the CHE amendments, for 

which CARB seeks a full authorization, 

meet the criteria of section 209(e) for a 

full authorization. 

IV. Procedures for Public Participation 

If a hearing is held, the Agency will 

make a verbatim record of the 

proceedings. Interested parties may 

arrange with the reporter at the hearing 

to obtain a copy of the transcript at their 

own expense. Regardless of whether a 

public hearing is held, EPA will keep 

the record open until July 21, 2014. 

Upon expiration of the comment period, 

the Administrator will render a decision 

on CARB’s request based on the record 

from the public hearing (if a hearing is 

conducted), all relevant written 

submissions, and other information that 

she deems pertinent. All information 

will be available for inspection at the 

EPA Air Docket No. EPA–HQ–OAR– 

2014–0060. 

Persons with comments containing 

proprietary information must 

distinguish such information from other 

comments to the greatest extent possible 

and label it as ‘‘Confidential Business 

Information’’ (‘‘CBI’’). If a person 

making comments wants EPA to base its 

decision on a submission labeled as CBI, 

then a non-confidential version of the 

document that summarizes the key data 

or information should be submitted to 

the public docket. To ensure that 

proprietary information is not 

inadvertently placed in the public 

docket, submissions containing such 

information should be sent directly to 

the contact person listed above and not 

to the public docket. Information 

covered by a claim of confidentiality 

will be disclosed by EPA only to the 

extent allowed, and according to the 

procedures set forth in 40 CFR Part 2. 

If no claim of confidentiality 

accompanies the submission when EPA 

receives it, EPA will make it available 

to the public without further notice to 

the person making comments. 

Dated: May 15, 2014. 

Christopher Grundler, 

Director, Office of Transportation and Air 

Quality, Office of Air and Radiation. 

[FR Doc. 2014–12009 Filed 5–27–14; 8:45 am] 

BILLING CODE 6560–50–P 

ENVIRONMENTAL PROTECTION 

AGENCY 

[FRL–9911–34–OAR] 

California State Nonroad Engine 

Pollution Control Standards; Small OffRoad Engines Regulation; Request for 

Within-the-Scope and Full 

Authorization; Opportunity for Public 

Hearing and Comment 

AGENCY: Environmental Protection 

Agency (EPA). 

ACTION: Notice. 

SUMMARY: The California Air Resources 

Board (CARB) has notified the 

Environmental Protection Agency (EPA) 

that it has adopted amendments to its 

spark-ignited (SI) Small Off-Road 

Engines (SORE) regulation (2008 SORE 

amendments). By letter dated December 

2, 2013, ARB asked that EPA authorize 

these amendments pursuant to section 

the Clean Air Act. CARB seeks 

confirmation that the amendments are 

within the scope of a prior authorization 

issued by EPA, or, in the alternative, 

that the amendments merit full 

authorization. This notice announces 

that EPA has tentatively scheduled a 

public hearing to consider California’s 

authorization request for the 2008 SORE 

amendments, and that EPA is now 

accepting written comment on the 

request. 

DATES: EPA has tentatively scheduled a 

public hearing concerning CARB’s 

request on June 19, 2014, at 10 a.m. ET. 

EPA will hold a hearing only if any 

party notifies EPA by June 9, 2014 to 

express interest in presenting the agency 

with oral testimony. Parties wishing to 

present oral testimony at the public 

hearing should provide written notice to 

David Dickinson at the email address 

noted below. If EPA receives a request 

for a public hearing, that hearing will be 

held at 1310 L Street NW., Washington, 

DC 20005. If EPA does not receive a 


emcdonald on DSK67QTVN1PROD with NOTICES
Federal Register / Vol. 79, No. 102 / Wednesday, May 28, 2014 / Notices 30611 

1The federal term ‘‘nonroad’’ and the California 

term ‘‘off-road’’ are used interchangeably. 

2 60 FR 37440 (July 20, 1995). 

3 65 FR. 69763 (November 20, 2000). 

4 65 FR 69767 (November 20, 2000); 68 FR 65702 

(November 21, 2003). 

5 75 FR 8056 (February 23, 2010). 

6 71 FR 75536 (December 15, 2006). 

7The specific regulatory text for the 2008 

amendments is codified at title 13, California Code 

of Regulations (CCR), sections 2401, 2403, 2404, 

Continued 

request for a public hearing, then EPA 

will not hold a hearing, and instead will 

consider CARB’s request based on 

written submissions to the docket. Any 

party may submit written comments 

until July 21, 2014. 

Any person who wishes to know 

whether a hearing will be held may call 

David Dickinson at (202) 343–9256 on 

or after June 13, 2014. Submit your 

comments, identified by Docket ID No. 

EPA–HQ–OAR–2014–0036, by one of 

the following methods: 

• Online at http:// 

www.regulations.gov: Follow the Online 

Instructions for Submitting Comments. 

• Email: a-and-r-docket@epa.gov. 

• Fax: (202) 566–9744. 

• Mail: Air and Radiation Docket, 

Docket ID No. EPA–HQ–OAR–2014– 

0036, U.S. Environmental Protection 

Agency, Mail code: 6102T, 1200 

Pennsylvania Avenue NW., Washington, 

DC 20460. Please include a total of two 

copies. 

• Hand Delivery: EPA Docket Center, 

Public Reading Room, EPA West 

Building, Room 3334, 1301 Constitution 

Avenue NW., Washington, DC 20460. 

Such deliveries are only accepted 

during the Docket’s normal hours of 

operation, and special arrangements 

should be made for deliveries of boxed 

information. 

Online Instructions for Submitting 

Comments: Direct your comments to 

Docket ID No. EPA–HQ–OAR–2014– 

0036. EPA’s policy is that all comments 

we receive will be included in the 

public docket without change and may 

be made available online at http:// 

www.regulations.gov, including any 

personal information provided, unless 

the comment includes information 

claimed to be Confidential Business 

Information (CBI) or other information 

whose disclosure is restricted by statute. 

Do not submit information that you 

consider to be CBI or otherwise 

protected through http:// 

www.regulations.gov or email. The 

http://www.regulations.gov Web site is 

an ‘‘anonymous access’’ system, which 

means EPA will not know your identity 

or contact information unless you 

provide it in the body of your comment. 

If you send an email comment directly 

to EPA without going through http:// 

www.regulations.gov, your email 

address will automatically be captured 

and included as part of the comment 

that is placed in the public docket and 

made available on the Internet. If you 

submit an electronic comment, EPA 

recommends that you include your 

name and other contact information in 

the body of your comment and with any 

disk or CD–ROM you submit. If EPA 

cannot read your comment due to 

technical difficulties and cannot contact 

you for clarification, EPA may not be 

able to consider your comment. 

Electronic files should avoid the use of 

special characters, any form of 

encryption, and be free of any defects or 

viruses. For additional information 

about EPA’s public docket visit the EPA 

Docket Center homepage at http:// 

www.epa.gov/epahome/dockets.htm. 

EPA will make available for public 

inspection materials submitted by 

CARB, written comments received from 

any interested parties, and any 

testimony given at the public hearing. 

Materials relevant to this proceeding are 

contained in the Air and Radiation 

Docket and Information Center, 

maintained in Docket ID No. EPA–HQ– 

OAR–2014–0036. Publicly available 

docket materials are available either 

electronically through http:// 

www.regulations.gov or in hard copy at 

the Air and Radiation Docket in the EPA 

Headquarters Library, EPA West 

Building, Room 3334, located at 1301 

Constitution Avenue NW., Washington, 

DC. The Public Reading Room is open 

to the public on all federal government 

work days from 8:30 a.m. to 4:30 p.m.; 

generally, it is open Monday through 

Friday, excluding holidays. The 

telephone number for the Reading Room 

is (202) 566–1744. The Air and 

Radiation Docket and Information 

Center’s Web site is http://www.epa.gov/ 

oar/docket.html. The electronic mail 

(email) address for the Air and 

Radiation Docket is: a-and-rDocket@epa.gov, the telephone number 

is (202) 566–1742, and the fax number 

is (202) 566–9744. An electronic version 

of the public docket is available through 

the federal government’s electronic 

public docket and comment system. 

You may access EPA dockets at http:// 

www.regulations.gov. After opening the 

http://www.regulations.gov Web site, 

enter, in the ‘‘Enter Keyword or ID’’ fillin box to view documents in the record. 

Although a part of the official docket, 

the public docket does not include 

Confidential Business Information 

(‘‘CBI’’) or other information whose 

disclosure is restricted by statute. 

EPA’s Office of Transportation and 

Air Quality also maintains a Web page 

that contains general information on its 

review of California waiver and 

authorization requests. Included on that 

page are links to prior waiver and 

authorization Federal Register notices. 

The page can be accessed at http://

www.epa.gov/otaq/cafr.htm. 

FOR FURTHER INFORMATION CONTACT: 

David Dickinson, Attorney-Advisor, 

Compliance Division, Office of 

Transportation and Air Quality, U.S. 

Environmental Protection Agency, 1200 

Pennsylvania Avenue (6405J) NW., 

Washington, DC 20460. Telephone: 

(202) 343–9256. Fax: (202)343–2804. 

Email: Dickinson.david@epa.gov. 

SUPPLEMENTARY INFORMATION: 

I. California’s SORE Regulation 

Small off-road engines and 

equipment 1 are rated at or below 19 

kilowatts (kW) (25 horsepower (hp)). 

The vast majority of engines covered by 

the SORE regulations are SI engines that 

are used to power a broad range of 

equipment, including lawn mowers, leaf 

blowers, generators, and small 

industrial equipment. Exhaust and 

evaporative emissions from these 

engines are a significant source of 

hydrocarbons and oxides of nitrogen, 

pollutants that contribute to smog 

problems in California. 

CARB promulgated its first SORE 

regulations in 1992 and amended them 

in 1993. EPA authorized the regulations, 

as amended, on July 5, 1995.2 CARB 

further amended these regulations in 

1994, 1995, and 1996, and EPA 

confirmed all the amendments to be 

within the scope of the prior approval 

on November 9, 2000.3 CARB again 

amended the SORE regulations in 1998, 

this time requesting within-the-scope 

determination for all but one of the 

amendments, for which full 

authorization was requested. EPA 

issued its within-the-scope 

determination on November 9, 2000, for 

these former amendments, and a full 

authorization on November 10, 2003, for 

the latter amendment.4 In 2000 and 

again in 2004, CARB amended the SORE 

regulations to more closely align with 

the federal SORE program. EPA 

confirmed that the 2000 amendments 

were within the scope of the previously 

granted SORE authorization in 

February, 2010, and also granted a full 

authorization for the 2004 amendments 

to standards and test procedures for 

certain nonroad compression ignition 

engines.5 EPA issued a full 

authorization for CARB’s 2004 

amendments to the SI SORE regulations 

on December 11, 2006.6

CARB adopted the 2008 SORE 

amendments on November 21, 2008.7


emcdonald on DSK67QTVN1PROD with NOTICES
30612 Federal Register / Vol. 79, No. 102 / Wednesday, May 28, 2014 / Notices 

2405, 2406, 2408, 2408.1 and 2409 (see enclosure 

6 to CARB’s December 2, 2013 request). California’s 

Office of Administrative Law formally approved the 

rulemaking on April 5, 2010 and the regulations 

became effective on May 5, 2010. 

8EPA’s most recent authorizations for CARB’s 

SORE regulations can be found at 71 FR 75536 

(December 15, 2006) and 75 FR 8056 (February 23, 

2010). 

9 59 FR 36969 (July 20, 1994). 

10 62 FR 67733 (December 30, 1997). The 

applicable regulations are now in 40 CFR part 1074, 

subpart B, § 1074.105. 

11 59 FR 36969 (July 20, 1994). 

The 2008 SORE amendments made 

three further changes to California’s 

SORE regulations. First, California 

modified certification emissions credits 

to expire five years after creation, and 

permitted the generation of certification 

emissions credits through the 

production of professional grade zeroemissions equipment. Second, the 

amendments eliminated production 

emissions credits, and provided 

manufacturers with the option to 

convert production emissions credits 

into certification emissions credits until 

2010. Third, manufacturers were 

permitted to use a certification fuel with 

up to ten volume percent ethanol 

content, provided that the same fuel is 

used for certification with the EPA. 

By letter dated December 2, 2013, 

CARB submitted a request to EPA 

pursuant to section 209(e) of the Clean 

Air Act (CAA or the Act) for 

authorization of its 2008 SORE 

amendments. CARB seeks EPA’s 

confirmation that the 2008 SORE 

amendments fall within the scope of 

EPA’s previous authorizations,8 or, in 

the alternate, a full authorization for 

those amendments. 

II. Clean Air Act Nonroad Engine and 

Vehicle Authorizations 

Section 209(e)(1) of the CAA prohibits 

states and local governments from 

adopting or attempting to enforce any 

standard or requirement relating to the 

control of emissions from new nonroad 

vehicles or engines. The Act also 

preempts states from adopting and 

enforcing standards and other 

requirements related to the control of 

emissions from non-new nonroad 

engines or vehicles. Section 209(e)(2), 

however, requires the Administrator, 

after notice and opportunity for public 

hearing, to authorize California to 

enforce such standards and other 

requirements, unless EPA makes one of 

three findings. In addition, other states 

with air quality attainment plans may 

adopt and enforce such regulations if 

the standards, and implementation and 

enforcement procedures, are identical to 

California’s standards. On July 20, 1994, 

EPA promulgated a rule that sets forth, 

among other things, regulations 

providing the criteria, as found in 

section 209(e)(2), which EPA must 

consider before granting any California 

authorization request for new nonroad 

engine or vehicle emission standards.9

EPA revised these regulations in 1997.10

The authorization criteria are (1) 

whether California’s protectiveness 

determination that its standards, in the 

aggregate, are at least as protective of 

public health and welfare as comparable 

federal standards is arbitrary and 

capricious; (2) California does not need 

such standards to meet compelling and 

extraordinary conditions; or (3) The 

California standards and accompanying 

enforcement procedures are not 

consistent with section 209 of the Act. 

As stated in the preamble to the 1994 

rule, EPA has historically interpreted 

the section 209(e)(2)(iii) ‘‘consistency’’ 

inquiry to require, at minimum, that 

California standards and enforcement 

procedures be consistent with section 

209(a), section 209(e)(1), and section 

209(b)(1)(C) (as EPA has interpreted that 

subsection in the context of section 

209(b) motor vehicle waivers).11

In order to be consistent with section 

209(a), California’s nonroad standards 

and enforcement procedures must not 

apply to new motor vehicles or new 

motor vehicle engines. To be consistent 

with section 209(e)(1), California’s 

nonroad standards and enforcement 

procedures must not attempt to regulate 

engine categories that are permanently 

preempted from state regulation. To 

determine consistency with section 

209(b)(1)(C), EPA typically reviews 

nonroad authorization requests under 

the same ‘‘consistency’’ criteria that are 

applied to motor vehicle waiver 

requests. Pursuant to section 

209(b)(1)(C), the Administrator shall not 

grant California a motor vehicle waiver 

if she finds that California ‘‘standards 

and accompanying enforcement 

procedures are not consistent with 

section 202(a)’’ of the Act. Previous 

decisions granting waivers and 

authorizations have noted that state 

standards and enforcement procedures 

are inconsistent with section 202(a) if: 

(1) There is inadequate lead time to 

permit the development of the necessary 

technology giving appropriate 

consideration to the cost of compliance 

within that time, or (2) the federal and 

state testing procedures impose 

inconsistent certification requirements. 

If California amends regulations that 

EPA has already authorized, California 

can seek EPA confirmation that the 

amendments are within the scope of the 

previous authorization. A within-thescope confirmation, without a full 

authorization review, is permissible if 

three conditions are met. First, the 

amended regulations must not 

undermine California’s determination 

that its standards, in the aggregate, are 

as protective of public health and 

welfare as applicable federal standards. 

Second, the amended regulations must 

not affect consistency with section 

202(a) of the Act. Third, the amended 

regulations must not raise any ‘‘new 

issues’’ affecting EPA’s prior 

authorizations. 

III. EPA’s Request for Comments 

As stated above, EPA is offering the 

opportunity for a public hearing, and is 

requesting written comment on issues 

relevant to a within-the-scope analysis. 

Specifically, we request comment on 

whether California’s 2008 SORE 

amendments: (1) Undermine 

California’s previous determination that 

its standards, in the aggregate, are at 

least as protective of public health and 

welfare as comparable federal standards; 

(2) affect the consistency of California’s 

requirements with section 209 of the 

Act; or (3) raise any other new issues 

affecting EPA’s previous waiver or 

authorization determinations. 

Should any party believe that the 

amendments are not within the scope of 

the previous authorization, EPA also 

requests comment on whether the 2008 

SORE amendments meet the criteria for 

a full authorization. Specifically, we 

request comment on: (a) Whether 

CARB’s determination that its 

standards, in the aggregate, are at least 

as protective of public health and 

welfare as applicable federal standards 

is arbitrary and capricious; (b) whether 

California needs such standards to meet 

compelling and extraordinary 

conditions; and (c) whether California’s 

standards and accompanying 

enforcement procedures are consistent 

with section 209 of the Act. 

IV. Procedures for Public Participation 

If a hearing is held, the Agency will 

make a verbatim record of the 

proceedings. Interested parties may 

arrange with the reporter at the hearing 

to obtain a copy of the transcript at their 

own expense. Regardless of whether a 

public hearing is held, EPA will keep 

the record open until July 21, 2014. 

Upon expiration of the comment period, 

the Administrator will render a decision 

on CARB’s request based on the record 

from the public hearing, if any, all 

relevant written submissions, and other 

information that she deems pertinent. 

All information will be available for 

inspection at the EPA Air Docket No. 

EPA–HQ–OAR–2014–0036. 


emcdonald on DSK67QTVN1PROD with NOTICES
Federal Register / Vol. 79, No. 102 / Wednesday, May 28, 2014 / Notices 30613 

1 42 U.S.C. 9604(i)(2)(A). 

2 42 U.S.C. 9604(i)(2)(B). 

Persons with comments containing 

proprietary information must 

distinguish such information from other 

comments to the greatest extent possible 

and label it as ‘‘Confidential Business 

Information’’ (‘‘CBI’’). If a person 

making comments wants EPA to base its 

decision on a submission labeled as CBI, 

then a non-confidential version of the 

document that summarizes the key data 

or information should be submitted to 

the public docket. To ensure that 

proprietary information is not 

inadvertently placed in the public 

docket, submissions containing such 

information should be sent directly to 

the contact person listed above and not 

to the public docket. Information 

covered by a claim of confidentiality 

will be disclosed by EPA only to the 

extent allowed, and according to the 

procedures set forth in 40 CFR Part 2. 

If no claim of confidentiality 

accompanies the submission when EPA 

receives it, EPA will make it available 

to the public without further notice to 

the person making comments. 

Dated: May 15, 2014. 

Christopher Grundler, 

Director, Office of Transportation and Air 

Quality, Office of Air and Radiation. 

[FR Doc. 2014–12017 Filed 5–27–14; 8:45 am] 

BILLING CODE 6560–50–P 

DEPARTMENT OF HEALTH AND 

HUMAN SERVICES 

Agency for Toxic Substances and 

Disease Registry 

Notice of the Revised Priority List of 

Hazardous Substances That Will Be 

Candidates for Toxicological Profiles 

AGENCY: Agency for Toxic Substances 

and Disease Registry (ATSDR), 

Department of Health and Human 

Services (HHS). 

ACTION: Notice. 

SUMMARY: The Comprehensive 

Environmental Response, 

Compensation, and Liability Act of 1980 

(CERCLA or Superfund), as amended by 

the Superfund Amendments and 

Reauthorization Act of 1986 (SARA), 

requires that ATSDR and the 

Environmental Protection Agency (EPA) 

prepare a Priority List of Hazardous 

Substances commonly found at facilities 

on the CERCLA National Priorities List 

(NPL). The Priority List of Hazardous 

Substances includes substances that 

have been determined to be of greatest 

public health concern to persons at or 

near NPL sites. CERCLA, as amended, 

also requires that the Priority List of 

Hazardous Substances be revised 

periodically. 

This announcement provides notice 

that a revised Priority List of 275 

Hazardous Substances has been 

developed and is now available. 

CERCLA, as amended, also requires 

ATSDR to prepare and to periodically 

revise toxicological profiles on 

hazardous substances included in the 

priority list. Thus, each priority list 

substance is a potential toxicological 

profile subject, as well as a candidate for 

identification of priority data needs. 

In addition to the Priority List of 

Hazardous Substances, ATSDR has 

developed a Completed Exposure 

Pathway Site Count Report. This report 

lists the number of sites or events at 

which ATSDR is involved and wherein 

a substance has been found in a 

completed exposure pathway (CEP). 

Address for Printed Copy: Requests 

for a printed copy of the 2013 Priority 

List of Hazardous Substances and 

Support Document, including the CEP 

report, should be submitted to Ms. 

Nickolette Roney, Division of 

Toxicology and Human Health Sciences, 

ATSDR, Mail Stop F–57, 1600 Clifton 

Road, NE., Atlanta, GA 30333. 

Electronic Availability: The 2013 

Priority List of Hazardous Substances 

and Support Document are posted on 

ATSDR’s Web site located at 

www.atsdr.cdc.gov/SPL. The CEP Report 

is posted at www.atsdr.cdc.gov/CEP. 

FOR FURTHER INFORMATION CONTACT: Ms. 

Nickolette Roney, Division of 

Toxicology and Human Health Sciences, 

ATSDR, 1600 Clifton Road NE., Mail 

Stop F–57, Atlanta, GA 30333, 

telephone 800–232–4636. 

This is an informational notice only; 

comments are not being solicited at this 

time. 

SUPPLEMENTARY INFORMATION: CERCLA 

establishes certain requirements for 

ATSDR and EPA with regard to 

hazardous substances most commonly 

found at facilities on the CERCLA NPL. 

Section 104(i)(2)(A) of CERCLA, as 

amended,1 requires that ATSDR and 

EPA prepare a list, in order of priority, 

of at least 100 hazardous substances 

most commonly found at facilities on 

the NPL and which, in the agencies’ sole 

discretion, pose the most significant 

potential threats to human health (see 

also 52 FR 12866, April 17, 1987). 

CERCLA section 104(i)(2)(B) 2 also 

requires the agencies to revise the 

priority list to include 100 or more 

additional hazardous substances (see 

also 53 FR 41280, October 20, 1988), 

and to include at least 25 additional 

hazardous substances in each of the 

three successive years following the 

1988 revision (see 54 FR 43615, October 

26, 1989; 55 FR 42067, October 17, 

1990; and 56 FR 52166, October 17, 

1991). CERCLA section 104(i)(2)(B) 

further requires ATSDR and EPA at least 

annually to revise the list to include any 

additional hazardous substances that 

have been determined to pose the most 

significant potential threat to human 

health. 

In 1995, the agencies, recognizing the 

stability of this listing activity, altered 

the priority list publication schedule (60 

FR 16478, March 30, 1995). As a result, 

the substance priority list is now on a 

2-year publication schedule, with 

annual informal review and revision. 

Each substance on the Priority List of 

Hazardous Substances is a potential 

subject of a toxicological profile 

prepared by ATSDR and, subsequently, 

a candidate for the identification of 

priority data needs. 

The ranking of substances on the 

priority list is based on an algorithm 

that consists of three criteria, weighted 

equally and combined to result in the 

total score. The three criteria are: (1) 

Frequency of occurrence at NPL sites; 

(2) toxicity; and (3) potential for human 

exposure. The site-specific information 

used to develop the priority list has 

been collected from ATSDR public 

health assessments and from site-file 

data packages used to develop the 

public health assessments. Since the 

development of the 2011 substance 

priority list, additional site specific 

information has been collected. The 

new information may include more 

recent NPL frequency-of-occurrence 

data, additional environmental media 

concentration data, and more 

information on exposure to substances 

at NPL sites. Using these additional 

data, one substance has been replaced 

on the list of 275 substances since the 

2011 publication. Changes in the order 

of substances appearing on the Priority 

List of Hazardous Substances will be 

reflected in program activities that rely 

on the list for guiding future activities. 

Using the current algorithm, a total of 

848 candidate substances have been 

analyzed and ranked. Of these 

candidates, the 275 substances on the 

priority list may in the future become 

the subject of toxicological profiles. 

Additional information on the 

existing methodology used in the 

development of the Priority List of 

Hazardous Substances can be found in 

the Support Document and in the abovereferenced Federal Register notices. 

In addition to the revised priority list, 

ATSDR is also releasing a revised 


emcdonald on DSK67QTVN1PROD with NOTICES