6560-50-P 

ENVIRONMENTAL PROTECTION AGENCY 

40 CFR Part 58 

[EPA–HQ–OAR–2006–0735; FRL– ] 

RIN 2060–AP77

Revisions to Lead Ambient Air Monitoring Requirements 

AGENCY: Environmental Protection Agency (EPA). 

ACTION: Proposed rule. 

SUMMARY: The EPA issued a final rule on November 12, 2008,

(effective date January 12, 2009) that revised the National 

Ambient Air Quality Standards (NAAQS) for lead and associated 

monitoring requirements. This action proposes revisions to the 

monitoring requirements in that final rule pertaining to where 

state and local monitoring agencies (“monitoring agencies”) 

would be required to conduct lead monitoring. 

DATES: Comments must be received on or before [insert date 45 

days after date of publication in the Federal Register]. 

ADDRESSES: Submit your comments, identified by Docket ID No. 

EPA-HQ-OAR-2006-0735 by one of the following methods: 

• http://www.regulations.gov: Follow the on-line 

instructions for submitting comments. 

• Email: a-and-r-Docket@epa.gov. 

• Fax: 202-566-9744. 

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• Mail: Docket No. EPA-HQ-OAR-2006-0735, Environmental 

Protection Agency, Mail Code 2822T, 1200 Pennsylvania Ave., 

NW., Washington, DC 20460. Please include a total of two 

copies. In addition, please mail a copy of your comments 

on the information collection provisions to the Office of 

Information and Regulatory Affairs, Office of Management 

and Budget (OMB), Attn: Desk Officer for EPA, 725 17

th St., 

NW, Washington, DC 20503. 

• Hand Delivery: Docket No. EPA-HQ-OAR-2006-0735, 

Environmental Protection Agency, EPA West, Room 3334, 1301 

Constitution Ave., NW, Washington, DC. Such deliveries are 

only accepted during the Docket’s normal hours of 

operation, and special arrangements should be made for 

deliveries of boxed information. 

Instructions: Direct your comments to Docket ID No. EPA-HQOAR-2006-0735. The EPA’s policy is that all comments received 

will be included in the public docket without change and may be 

made available online at 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 www.regulations.gov or email. 

The www.regulations.gov website is an “anonymous access” system, 

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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 www.regulations.gov, your email address will be 

automatically 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. 

Docket: All documents in the docket are listed in the 

www.regulations.gov index. Although listed in the index, some 

information is not publicly available, e.g., CBI or other 

information whose disclosure is restricted by statute. Certain 

other material, such as copyrighted material, will be publicly 

available only in hard copy. Publicly available docket 

materials are available either electronically in 

www.regulations.gov or in hard copy at the Air and Radiation 
4 

Docket and Information Center, EPA/DC, EPA West, Room 3334, 1301 

Constitution Ave., NW, Washington, DC. The Public Reading Room 

is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, 

excluding legal holidays. The telephone number for the Public 

Reading Room is (202) 566-1744, and the telephone number for the 

Air and Radiation Docket and Information Center is (202) 566-

1742.

FOR FURTHER INFORMATION CONTACT: For further information 

contact Mr. Kevin Cavender, Air Quality Assessment Division, 

Office of Air Quality Planning and Standards, U.S. Environmental 

Protection Agency, Mail Code C304-06, Research Triangle Park, NC 

27711; telephone: 919-541-2364; fax: 919-541-1903; email: 

cavender.kevin@epa.gov. 

SUPPLEMENTARY INFORMATION: 

I. General Information 

A. What should I consider as I prepare my comments for

 EPA?

1. Submitting CBI. Do not submit this information to EPA 

through www.regulations.gov or email. Clearly mark the part or 

all of the information that you claim to be CBI. For CBI 

information in a disk or CD-ROM that you mail to EPA, mark the 

outside of the disk or CD-ROM as CBI and then identify 

electronically within the disk or CD-ROM the specific 

information that is claimed as CBI. In addition to one complete 

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5 

version of the comment that includes information claimed as CBI, 

a copy of the comment that does not contain the information 

claimed as CBI must be submitted for inclusion in the public 

docket. Information so marked will not be disclosed except in 

accordance with procedures set forth in 40 CFR part 2. 

 2. Tips for Preparing Your Comments. When submitting 

comments, remember to: 

• Identify the rulemaking by docket number and other 

identifying information (subject heading, Federal Register

date, and page number). 

• Follow directions – the agency may ask you to respond to 

specific questions or organize comments by referencing a 

Code of Federal Regulations (CFR) part or section number. 

• Explain why you agree or disagree, suggest alternatives, 

and substitute language for your requested changes.

• Describe any assumptions and provide any technical 

information and/or data that you used. 

• If you estimate potential costs or burdens, explain how you 

arrived at your estimate in sufficient detail to allow for 

it to be reproduced. 

• Provide specific examples to illustrate your concerns, and 

suggest alternatives. 
6 

• Explain your views as clearly as possible, avoiding the use 

of profanity or personal threats. 

• Make sure to submit your comments by the comment period 

deadline identified. 

B. Availability of Related Information

A number of documents relevant to this rulemaking, 

including the notice of final rulemaking (73 FR 66964), the 

notice of proposed rulemaking (73 FR 29184), the advance notice 

of proposed rulemaking (72 FR 71488), the Air Quality Criteria 

for Lead (Criteria Document) (USEPA, 2006), the Staff Paper, and 

other related technical documents are available on EPA’s Office 

of Air Quality Planning and Standards (OAQPS) Technology 

Transfer Network (TTN) website at 

http://www.epa.gov/ttn/naaqs/standards/lead/s_lead_index.html. 

These and other related documents are also available for 

inspection and copying in the EPA docket identified above. 

C. When would a public hearing occur?

If anyone contacts EPA requesting to speak at a public 

hearing concerning this proposed rule by [insert date 10 days 

after publication in the Federal Register], we will hold a 

public hearing on [insert date 15 days after publication in the 

Federal Register]. If [insert date 15 days after publication in 

the Federal Register] falls on a Friday, Saturday, or Sunday, 

the hearing will be held on the following Monday. Persons 

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Hearing Occur
7 

interested in presenting oral testimony at the hearing, or 

inquiring as to whether a hearing will be held, should contact 

Kevin A. Cavender at (919) 541–2364 at least 2 days in advance 

of the hearing. If a public hearing is held, it will be held at 

10 a.m. at the EPA’s campus located at 109 T.W. Alexander Drive 

in Research Triangle Park, NC, or an alternate site nearby. 

Under CAA section 307(d)(1)(V), the Administrator determines 

that the provisions of section 307(d) are applicable to this 

proposal and all the procedural requirements of section 307(d) 

will apply to it. 

D. How is this document organized?

 The information presented in this document is organized as 

follows: 

I. General Information 

 A. What should I consider as I prepare my comments

for EPA? 

 B. Availability of Related Information 

 C. When would a public hearing occur?

 D. How is this document organized?

II. Background 

III. Source-Oriented Monitoring Requirements 

A. Background on Source-Oriented Monitoring 

Requirements 

B. Issues With Source-Oriented Monitoring 

Requirements 

C. Reconsideration of Source-Oriented Monitoring 

Requirements 

IV. Monitoring of Airports

V. Non-Source-Oriented Monitoring Requirements 

A. Background on Non-Source-Oriented Monitoring 

Requirements 

B. Issues With Non-Source-Oriented Monitoring 

Requirements 

C. Reconsideration of Non-Source-Oriented Monitoring 

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Organized

Deleted: A. What Should I 

Consider as I Prepare My 

Comments¶

Deleted: C. When Would a 

Public Hearing Occur?¶

D. How is This Document 

Organized?¶
8 

Requirements 

VI. Increase in Lead Monitors and Timeline for Deploying 

New Monitors 

VII. Statutory and Executive Order Reviews 

 A. Executive Order 12866: Regulatory Planning and

Review 

 B. Paperwork Reduction Act 

 C. Regulatory Flexibility Act 

 D. Unfunded Mandates Reform Act 

 E. Executive Order 13132: Federalism 

 F. Executive Order 13175: Consultation and 

Coordination with Indian Tribal Governments 

 G. Executive Order 13045: Protection of Children 

From Environmental Health and Safety Risks 

 H. Executive Order 13211: Actions That Significantly 

Affect Energy Supply, Distribution or Use 

 I. National Technology Transfer and Advancement Act 

 J. Executive Order 12898: Federal Actions to 

Address Environmental Justice in Minority 

Populations and Low-Income Populations 

VIII. References 

 

II. Background 

The EPA issued a final rule on November 12, 2008, that 

revised the NAAQS for lead and associated ambient air lead

monitoring requirements (73 FR 66964, codified at 40 CFR part 

58). As part of the lead monitoring requirements, monitoring 

agencies are required to monitor ambient air near lead sources 

which are expected to or have been shown to have a potential to 

contribute to a 3-month average lead concentration in ambient 

air in excess of the level of the NAAQS. At a minimum, 

monitoring agencies must monitor near lead sources that emit 1.0 

ton per year (tpy) or more. However, this requirement can be 

waived by the EPA Regional Administrator if the monitoring 

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agency can demonstrate that the source will not contribute to a 

3-month average lead concentration in ambient air in excess of 

50 percent of the level of the NAAQS (based on historical 

monitoring data, modeling, or other means). 

Monitoring agencies are also currently required to conduct 

lead monitoring in large urban areas (identified as Core Based 

Statistical Areas, or CBSAs, as defined by the OMB) with a 

population of 500,000 people or more. The locations for these 

monitoring sites are intended to measure neighborhood-scale lead

concentrations in urban areas impacted by resuspended dust from 

roadways, closed industrial sources which previously were 

significant sources of lead, hazardous waste sites, construction 

and demolition projects, or other fugitive dust sources of lead. 

Following promulgation of the revised lead NAAQS and 

monitoring requirements, the Natural Resources Defense Council

(NRDC), the Missouri Coalition for the Environment Foundation, 

the Physicians for Social Responsibility, and the Coalition to 

End Childhood Lead Poisoning (“the Petitioners”) petitioned 

(NRDC, 2009) for a reconsideration of the lead emission rate at 

which monitoring is required (the “emission threshold,” 

currently 1.0 tpy). On July 22, 2009, the EPA granted the 

petition to reconsider aspects of the monitoring requirements 

(Jackson, 2009). In response to the petition, the EPA reviewed 

and reconsidered the monitoring requirements and is proposing 

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revisions to the requirements for both source-oriented and nonsource-oriented monitoring for lead. 

III. Source-Oriented Monitoring Requirements 

The EPA is proposing to change the lead emission threshold 

at which monitoring agencies are presumptively required to 

conduct lead monitoring near a lead source to 0.50 tpy from an 

emissions threshold of 1.0 tpy. The EPA is also seeking 

comments on alternative emission thresholds between 0.50 tpy to 

1.0 tpy. The following paragraphs discuss the issues 

considered, the proposed changes, and our rationale for the 

proposed changes to the source-oriented monitoring requirements. 

A. Background on Source-Oriented Monitoring Requirements

 In the final revisions to the lead NAAQS, the EPA noted 

that, due to the dramatic drop in lead concentrations since the 

phase-out of lead in motor vehicle gasoline, we expected 

concentrations of lead to approach the revised level of the lead

NAAQS primarily near sources of lead. Accordingly, the EPA 

required monitoring near lead emission sources such as lead

smelters, metallurgical operations, battery manufacturing, and 

other source categories that emit lead. 

The EPA also noted in the final NAAQS rulemaking that it is 

not practical to conduct monitoring at every lead emission 

source, nor is it likely that very small lead emission sources 

will cause ambient concentrations to exceed the promulgated 

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NAAQS. Therefore, the EPA performed an analysis to determine at 

what level of lead emissions (the “emissions threshold”) it may 

be possible for an emission source to cause ambient lead

concentrations to exceed the lead NAAQS (Cavender, 2008). This 

analysis looked at a range of levels and indicated that, under 

reasonable worst-case conditions, a 0.50 tpy lead source could 

cause ambient lead concentrations to exceed the revised lead

NAAQS. The EPA also noted that, by basing the monitoring 

requirements on worst-case conditions, the EPA would be “placing 

an unnecessary burden on monitoring agencies to evaluate or 

monitor around sources that may not have a significant potential 

to exceed the NAAQS.” As such, the EPA required monitoring 

agencies to take into account lead sources which are expected to 

or have been shown to contribute to a maximum lead concentration 

in ambient air in excess of the NAAQS including, and, at a 

minimum, to conduct lead monitoring [or request monitoring 

waivers as allowed for under 40 CFR part 58, Appendix D, 

paragraph 4.5(a)(ii)] near lead sources emitting 1.0 or more 

tpy. To account for lead sources emitting less than 1.0 tpy of 

lead that may have the potential to cause lead concentrations to 

exceed the lead NAAQS, the November 12, 2008, final rule 

provided the EPA Regional Administrators the authority to 

require additional monitoring beyond the minimum monitoring 

requirements where the likelihood of lead air quality violations 

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is significant or where the emissions density, topography, or 

population locations are complex and varied. The EPA projected 

the source-oriented portion of the network to be up to 135 

monitors based on these requirements and on information 

available at the time the final rule was published (i.e., the 

2002 National Emissions Inventory (NEI))

1. 

B. Issues With Source-Oriented Monitoring Requirements

The Petitioners cited several reasons for EPA to reconsider 

the lead monitoring emission threshold (NRDC, 2009). They noted 

that the finalized emission threshold of 1.0 tpy was above the 

proposed range of 200 to 600 kilograms per year and, therefore, 

argued that the EPA failed to provide for proper public comment 

on the 1.0 tpy threshold. They also argued that the selection 

of the 1.0 tpy emission threshold was arbitrary and capricious 

and that the EPA did not follow its own analysis. Finally, they 

argued that the 1.0 tpy emission threshold would not provide for 

an adequate margin of safety as required by the Clean Air Act. 

The EPA granted the petition to reconsider the monitoring 

emission threshold (Jackson, 2009), and this proposed rule 

reflects our reconsideration of the emission threshold. 

C. Reconsideration of Source-Oriented Monitoring Requirements

 

1 Note that the 2005 NEI is now available and the EPA has used the lead

emission estimates in the 2005 NEI for estimating the impact of these 

proposed revisions. Based on the 2005 NEI, 111 source-oriented monitoring 

sites would be required under the existing monitoring requirements. 

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Deleted: In addition to the 

petition to reconsider, the 

EPA has received informal 

feedback from members of the 

National Association of 

Clean Air Agencies (NACAA) 

monitoring subcommittee 

regarding monitoring of 

airports from which Pb is 

emitted as a result of the 

use of leaded aviation fuel 

(Cavender, 2009). These 

NACAA members believe that 

the final Pb NAAQS 

rulemaking inappropriately 

treats airports in the same 

manner as industrial Pb 

sources and claim that Pb 

emissions at airports will 

have a lesser impact on 

ambient Pb concentrations 

since the Pb emissions from 

airplanes taking off from or 

landing at airports are 

spread out over a larger 

area, unlike industrial 

sources where the emissions 

may be emitted from a few 

stacks.¶

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 The monitoring emission threshold was intended to identify 

lead sources which may have the potential to contribute to or 

approach an exceedance of the lead NAAQS and near which lead

monitoring should be conducted (or where a site-specific 

evaluation of the potential for the lead source to contribute to 

an exceedance of the lead NAAQS should be performed). The EPA’s 

analysis to determine the emission threshold relied on three 

different approaches. 

One of the three approaches relied on the use of existing 

lead monitoring data near lead sources. The EPA believes this 

approach provides the best information on the potential impact 

of lead sources on ambient lead concentrations because it uses 

actual source-oriented lead monitoring data from lead sources. 

As such, this approach was reevaluated as part of the EPA’s 

reconsideration using updated design-values based on the final 

data handling procedures contained in 40 CFR part 50 Appendix R. 

Under this approach, source-oriented lead monitors within 1 mile 

of a lead source (identified from the 2002 NEI) were identified. 

This group of sites was then narrowed down to sites near 

facilities emitting 1 tpy or more of lead into the ambient air, 

and then to sites which were only impacted by one lead emitting 

facility. Also, in cases where more than one monitor was 

identified within 1 mile of the same facility emitting 1 tpy or 

more of lead annually, the EPA only used the monitor measuring 

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Inventory (

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14 

the maximum lead concentration in the analysis. In this manner, 

the EPA identified seven monitor-facility pairs meeting the 

emissions and distance criteria. Using data in the Air Quality 

System (AQS) database (http://www.epa.gov/ttn/airs/airsaqs/) for 

the years 2001-2003, the EPA developed an estimate of the 

maximum 3-month average lead concentration for each monitoring 

site2. Next, EPA calculated a ratio of the maximum 3-month 

average concentration to the facility annual emissions (as 

identified in the 2002 NEI) to provide an estimate of the impact 

from the facility in units of micrograms per meter cubed (μg/m3)

per tpy. Dividing the level of the lead NAAQS (0.15 μg/m3) by 

this ratio provides an estimate of the annual emission level for 

the facility which would result in ambient lead concentrations 

just meeting the lead NAAQS, referred to here as a “sitespecific emission threshold” (see Table 1). 

Table 1. Data Used to Estimate Facility Impacts Based on 

Monitoring Data 

AQS Site 

Id 

Maximum 3-

Month Average 

Lead

Concentration 

(μg/m3) 

NEI 2002 

Facility 

Emission 

Rate 

(tpy) 

Ratio 

(μg/m3-

tpy) 

SiteSpecific 

Emission 

Threshold 

(tpy) 

011090003 1.2 4.5 0.27 0.56

171190010 0.33 1.3 0.25 0.59

290990013 1.8 58.8 0.03 4.90

340231003 0.23 1.7 0.14 1.11

 

2 The estimate of the maximum 3-month average lead concentration for this 

analysis was completed prior to promulgation of the final data handling rules 

contained in 40 CFR Part 50 Appendix R. As such, minor differences in the 

estimated maximum 3-month average lead concentration appear in the estimates 

presented below for the same time period.

Formatted Table

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Deleted: Pb

Deleted: Pb

Deleted: Pb

Deleted: Pb

Deleted: Pb

Deleted: 171190010

Deleted: 0.33

Deleted: 1.3

Deleted: 3

Deleted: 340231003

Deleted: 18

Deleted: 7

Deleted: 1

Deleted: 1.5

Deleted: 471870100

Deleted: 0.89

Deleted: 2.6

Deleted: 0.5

Deleted: 480850009

Deleted: 75

Deleted: 3.2

Deleted: 2

Deleted: 0.8
15 

420110717 0.24 4.8 0.05 3.00

471870100 0.93 2.6 0.36 0.42

480850009 0.75 3.2 0.23 0.64

This analysis shows that four of these seven lead sources 

support an emission threshold less than the emission threshold 

of 1.0 tpy set by the final rule on the revised lead NAAQS. 

As part of this reconsideration, the EPA evaluated the 

stability and sensitivity of the above analysis. To evaluate 

the stability of the site-specific emission threshold 

calculation, the EPA performed the same analysis for these same 

seven facilities based on the emission estimates from the 2002 

and 2005 NEI (Table 2) and estimated design values over the 

periods 2001-2003 and 2004-2006 (Table 3). Table 4 summarizes 

the site-specific emission thresholds calculated for these 

periods.

Table 2. NEI Emission Estimates 

AQS Site Id

NEI 

Facility 

ID

Facility Name

2002 NEI 

Facility 

Emission 

Rate

(tpy)

2005 NEI 

Facility 

Emission 

Rate

(tpy)

011090003 NEI18383 Sanders Lead 

Co

4.5 4.44

171190010 NEI55848 National 

Steel Corp -

Granite City 

Div

1.3 0.90

290990013 NEI34412 Doe Run 

Company, 

Herculaneum 

Smelter

58.8 28.09

340231003 NEINJ1603

1

Johnson 

Controls 

1.7 1.34

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Deleted: 1

Deleted: 1.5

Deleted: 011090003

Deleted: 1.20

Deleted: 4.5

Deleted: 5

Deleted: 290990013

Deleted: 1.29

Deleted: 58.8

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16 

Battery Group 

Inc

420110717 NEI117 East Penn Mfg 4.8 1.88

471870100 NEI715 MetalicoCollege 

Grove, Inc.

2.6 2.55

480850009 NEI6493 Gnb Metals 

Div

3.2 3.18

Table 3. Estimated Design Values Based on Alternative Years

AQS Site 

Id

2001-2003

Design Value 

(μg/m3)

2004-2006

Design Value 

(μg/m3)

011090003 1.2 1.16

171190010 0.33 0.43

290990013 1.8 1.44

340231003 0.23 0.32

420110717 0.24 0.20

471870100 0.93 --

3

480850009 0.75 0.77

Table 4. Estimated Site-Specific Emission Thresholds Based on 

Alternative Years

Site-Specific 

AQS Site Emission Threshold

Id 2002 2005

011090003 0.56 0.57

171190010 0.59 0.32

290990013 4.90 2.933

340231003 1.11 0.63

420110717 3.00 1.41

471870100 0.42 --

4

480850009 0.64 0.62

Minimum 0.42 0.32

Median 0.64 0.62

Maximum 4.90 2.93

 

3

The EPA notes that, for facilities where emissions have dramatically 

decreased in recent years, re-entrained lead from historical deposits may 

influence the emission threshold calculation to a greater extent than for 

facilities where lead emissions have remained constant.

4

Monitoring data at this site did not meet the minimum completeness 

requirements of 40 CFR part 50 Appendix R for this time period. No design 

value or site-specific emission factor was calculated for this time period.
17 

Table 4 shows that, in most cases, the calculated emission 

threshold remained fairly constant for a given facility over 

time, in general, varying by a factor of 2 or less. Sitespecific emission thresholds varied from 0.32 tpy to 4.9 tpy 

with a median of 0.63 tpy. 

The EPA notes that these metrics may be exaggerated by 

outliers due to the limited number of facilities being 

evaluated. As such, the EPA looked at how these metrics changed 

when the extreme sites (i.e., the highest and lowest emitting 

sources) were removed. Excluding site 290990013 resulted in a 

lowering of the upper range to 3 tpy and the median to 0.62 tpy, 

but did not affect the minimum (0.32 tpy). Excluding site 

171190010 increases the minimum to 0.42 and the median to 0.64 

tpy, but does not affect the maximum.

In the final rule, the EPA stated that an emission 

threshold of 1.0 tpy “is more likely to clearly identify sources 

that would contribute to exceedances of the NAAQS” as compared 

to a lower emission threshold. Upon further consideration and 

based on the site-specific emission thresholds estimated above, 

the EPA has decided to propose a revision to the emission 

threshold. Based on this sample of lead sources, it appears 

that lead sources that emit less than 1.0 tpy have the potential 

to cause ambient lead concentrations to exceed or approach the 

lead NAAQS. Monitoring agencies would not identify these 

Deleted: however, 

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in Table 1

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an

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threshold 
18 

sources based on a 1.0 tpy emission threshold. This could 

result in a number of areas with the potential to have lead

concentrations above the lead NAAQS not being properly monitored 

and could result in some areas where the NAAQS is exceeded not 

being identified as nonattainment for lead. 

The EPA has reconsidered the emission threshold and 

proposes to lower the emission threshold to a level of 0.50 tpy, 

which the EPA believes is consistent with the analysis 

documented for the final rule (Cavender, 2008) and the findings 

of this reconsideration. If this proposal is finalized, 

monitoring agencies would be required to conduct monitoring near 

lead sources that emit 0.50 tpy or greater, or request a waiver 

as allowed by 40 CFR part 58, Appendix D, paragraph 4.5(a)(ii). 

The EPA believes an emission threshold of 0.50 tpy would 

adequately identify those sources with the potential to exceed 

the NAAQS without placing undue burden on monitoring agencies. 

The EPA is also seeking comments and supporting information that 

could be used in setting an emission threshold lower than 0.5 

tpy as well as higher than 0.5 tpy.

In addition, the EPA is proposing to edit the wording of 

the source-oriented monitoring requirement [40 CFR part 58, 

Appendix D, paragraph 4.5(a)] for clarity. The EPA believes the 

edits are merely editorial and do not change the purpose and 

intent of the existing requirement.

Formatted: Indent: First line: 0.5"

Deleted: large 

Deleted: a 

Deleted: Pb

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would be contrary to the 

purpose of the NAAQS to 

protect public health with 

an adequate margin of safety 

and also to protect public 

welfare. As such, the

Deleted: performed 

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health 

Deleted: an adequate margin 

of safety.

Deleted: on 

Deleted: between 0.50 tpy and 

1.0 tpy, i.e., require 

monitoring near sources that 

emit Pb at some level 

between 0.50 tpy and 1.0 

tpy.¶

As discussed above, the EPA

has received comments from 

the NACAA monitoring 

subcommittee claiming that 

airports should not be 

treated in the same manner 

as industrial sources of Pb 

with regards to monitoring 

requirements (Cavender, 

2009). This perspective is 

based on the belief that Pb 

emissions at airports will 

have a lesser impact on offairport and on-airport 

ambient Pb concentrations 

because the Pb emissions 

from airplanes taking off 

from or landing at airports 

are spread out over a larger 

area resulting in greater 

dilution of ambient 

concentrations, unlike 

industrial sources where the 

bulk of emissions may be 

emitted from a few stacks 

resulting in relatively 

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19 

IV. Monitoring of Airports

In addition to the petition to reconsider, the EPA has 

received informal feedback from members of the National 

Association of Clean Air Agencies (NACAA) monitoring 

subcommittee regarding monitoring of airports from which lead is 

emitted as a result of the use of leaded aviation fuel 

(Cavender, 2009a). These NACAA members believe that the final 

lead NAAQS rulemaking inappropriately treats airports in the 

same manner as industrial lead sources and claim that lead

emissions at airports will have a lesser impact on ambient lead

concentrations since the lead emissions from airplanes taking 

off from or landing at airports are spread out over a larger 

area, unlike industrial sources where the emissions may be 

emitted from a few stacks.

The EPA has limited quantitative information with which to 

evaluate the impact on either on-airport or off-airport ambient 

lead concentrations from airports. One study conducted near the 

Santa Monica airport measured a maximum 3-month average lead

concentration of 0.1 μg/m3 near the runway blast fence (Cavender, 

2009b). Based on the 2002 lead emission estimate for the Santa 

Monica airport of 0.4 tpy (USEPA, 2008a), an estimated sitespecific emission threshold of 0.6 tpy can be calculated using 

the same procedures used to estimate a site-specific emission 

threshold as above [i.e., 0.15 μg/m3 /(0.1 μg/m3 / 0.4 tpy) = 0.6 

Deleted: Pb

Deleted: Pb

Deleted: Fine, 2007).

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20 

tpy]. This site-specific emission threshold (0.6 tpy) falls 

within the lower end of the range of specific emission 

thresholds calculated for industrial sources above (0.32 to 4.9

tpy) and does not support the case for different treatment of 

airports.

5 The EPA is not aware of similar studies where lead 

was monitored at or near the maximum impact area and does not 

believe there are sufficient data to develop or justify a 

separate emission threshold for airports.

6 As such, the EPA 

proposes to treat airports identically to other sources of lead, 

and require monitoring agencies to conduct lead monitoring [or 

request a monitoring waiver as allowed under 40 CFR part 58, 

Appendix D, paragraph 4.5(a)(ii)] at or near airports that emit 

0.50 tpy of lead, as is required for other sources of lead. 

The EPA estimates airport-specific lead inventories using a 

method similar to that used by the Federal Aviation

Administration (FAA) to estimate inventories of other criteria 

pollutants emitted by aircraft at airport facilities in its 

Emissions and Dispersion Modeling System (EDMS). The method EPA 

uses to calculate airport-specific lead inventories is briefly 

 

5

The EPA notes that “urban background lead” (typically 0.02-0.03 μg/m3) may 

have a higher impact on this estimate of the site-specific emission threshold 

than in the estimates made for industrial facilities since the urban 

background represents a higher percentage of the total lead concentration. 

Basing the calculation on just the impact from the airport would result in a 

higher site-specific emission threshold estimate.

6

EPA notes that additional information may become available regarding the 

Santa Monica airport lead study, or other similar studies, prior to the 

issuance of a final rule. If additional information does become available 

before this rule is finalized (e.g., a final study report on the Santa Monica 

airport), EPA will take such information into account.

Deleted: 50

Deleted: 7.5

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Deleted: on airport property 

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21 

described here and a more complete description is available in 

other documents (USEPA 2008a). The EPA’s method for calculating 

airport-specific lead inventories requires as input the 

following data: the activity of piston-engine aircraft at a 

facility, fuel consumption rates by these aircraft during the 

various modes of the landing and takeoff cycle (LTO), time in 

each mode (taxi/idle-out, takeoff, climb-out, approach, and 

taxi/idle-in), the concentration of lead in the fuel, and the 

retention of lead in the engine and oil. We use information 

from national databases to supply this information. The data 

inputs for which states or local authorities may be able to 

obtain airport-specific data are:

1) Airport-specific LTO activity for piston-powered aircraft, 

including the fraction of piston-engine activity conducted 

by single- versus twin-engine aircraft. There are no 

national databases that provide airport-specific LTO 

activity data for piston-engine aircraft separately from 

turbojet and turboprop aircraft (turboprop and turbojet 

powered aircraft use jet fuel, which does not contain

lead). Some airport facilities collect this information 

and states may use these data to calculate airport-specific 

lead inventories.

2) The time spent in each mode of the LTO cycle. EPA uses the 

EDMS scenario property of International Civil Aviation 
22 

Organization/USEPA Default - Times in Mode, with a 16-

minute taxi-in/taxi-out time according to EPA’s Procedures 

for Emission Inventory Preparation, Volume IV: Mobile 

Sources, 1992. We are requesting airport-specific 

information for these times in each mode of the LTO cycle. 

We also request information regarding the time spent in 

run-up checks conducted by piston-engine aircraft prior to 

take-off. This mode of operation is not currently included 

in EPA’s airport-specific lead inventories.

3) Other data inputs for the airport-specific lead inventory 

calculation for which states or local authorities may 

provide airport-specific information include the 

concentration of lead in the aviation gasoline supplied at 

an airport, and the fraction of lead in fuel that is 

retained in the engine and oil, and actual fuel consumption 

rates by the piston-engine aircraft operating at specific 

airports.

The EPA identified 55 airports that may exceed the proposed 

0.50 tpy emission threshold. Under this proposed rule, state 

and local monitoring agencies would be required to monitor these 

airports, request a waiver as allowed under 40 CFR part 58 

Appendix D (by performing dispersion modeling to demonstrate 

that estimated maximum lead concentrations would be less than 50

percent of the lead NAAQS), or demonstrate that the actual 
23 

emissions from a given airport are less than 0.50 tpy (by using 

site-specific values for the factors identified above in lieu of 

the national average values used by the EPA). The EPA is 

requesting airport-specific data inputs that states or other 

local authorities could provide to EPA, particularly for 

airports that would be subject to lead monitoring in the context 

of this proposed rule.

The EPA solicits comments on the availability of other data 

that may be useful in considering an alternative emission 

threshold for airports. The Agency also seeks comment on 

whether EPA should consider other factors or criteria that might 

be useful in determining if a different approach is appropriate 

for identifying those airports that have the potential to 

approach or contribute to violations of the lead NAAQS. For 

example, the EPA could require monitoring at airports that the 

EPA determines have the potential to cause increased ambient 

lead concentrations approaching or contributing to violations of 

the NAAQS based on criteria including the estimated lead

emissions and other factors such as the number of runways where 

piston-engine aircraft operate. However, we do not currently

have information regarding the impact of airport-specific 

attributes on ambient lead concentrations. The EPA solicits 

comments on alternative approaches including the factors that 

could be considered in identifying airports that may require 

Deleted: this issue, on 

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24 

monitoring. We also request data to support the relationship 

between airport-specific factors or attributes and ambient lead

concentrations. 

V. Non-Source-Oriented Monitoring Requirements 

 The EPA is proposing to replace the current non-sourceoriented monitoring approach with the requirement for lead

monitoring at the national multi-pollutant monitoring network 

known as NCore. The following paragraphs discuss the issues 

considered, the proposed changes, and our rationale for the 

proposed changes to the non-source-oriented monitoring 

requirements. 

A. Background on Non-Source-Oriented Monitoring

 Requirements

 As part of the November 2008 revisions to the lead NAAQS, 

the EPA required one lead monitor site in each CBSA with a 

population of 500,000 people or more - leading to 101 monitors. 

These monitors are to be located to measure neighborhood scale 

(as described in 40 CFR part 58, Appendix D, paragraph 

1.2(b)(3)) lead concentrations in urban areas impacted by resuspended dust from roadways, closed industrial sources which 

previously were significant sources of lead, hazardous waste 

sites, construction and demolition projects, or other fugitive 

dust sources of lead. 

Deleted: In addition, the EPA 

is proposing to edit the 

wording of the sourceoriented monitoring 

requirement [40 CFR part 58, 

Appendix D, paragraph 

4.5(a)] for clarity. The 

EPA believes the edits are 

merely editorial and are 

consistent with the purpose 

and intent of the existing 

requirement.¶

I

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Deleted: Core Based 

Statistical Areas (

Deleted: )

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25 

The EPA had proposed (73 FR 29184) and taken comment on a 

smaller non-source-oriented lead monitoring network that 

included 1 monitor in each CBSA with a population of 1,000,000 

or more people, located to measure typical neighborhood scale 

lead concentrations in urban areas – which would have required 

50 monitors. The EPA noted that data from these non-sourceoriented monitors would be helpful in better characterizing 

population exposure to ambient air related lead and may assist 

in determining nonattainment boundaries. 

Concerns were raised during review of the draft final 

notice that non-inventoried lead sources in urban areas, such as 

closed industrial sources, hazardous waste sites, and 

construction and demolition projects could potentially result in 

ambient lead concentrations in excess of the lead NAAQS. To 

address these concerns, the EPA modified the siting criteria to 

require non-source-oriented monitors to be sited to evaluate 

these non-inventoried lead sources. The EPA also lowered the 

population threshold from requiring monitoring at CBSAs with a 

population of 1,000,000 people or more to requiring monitoring 

at CBSAs with a population of 500,000 people or more. 

B. Issues With Non-Source-Oriented Monitoring Requirements

 Some sources of lead which are not in the current NEI that 

could result in ambient lead concentrations in excess of the 

lead NAAQS have been identified (USEPA, 2008b). However, as 

Deleted: s

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26 

currently written, it is not clear that the non-source-oriented 

monitoring requirements would result in monitors near such noninventoried sources. The non-source-oriented monitors are to be 

sited as neighborhood scale monitors. Yet, lead concentrations 

drop off rapidly with distance away from a source, such that it 

is unlikely that non-source-oriented monitors would identify the 

maximum lead concentration near non-inventoried sources where 

the lead NAAQS could be exceeded. Furthermore, locations near 

non-inventoried sources outside of CBSAs with a population of 

500,000 people or more would not be addressed by the current 

non-source-oriented requirements and, as such, these sources 

would not necessarily be monitored. The final siting 

requirements also would not support the measurement of trends in 

typical urban lead concentrations, one of EPA’s original 

objectives. 

C. Reconsideration of Non-Source-Oriented Monitoring

 Requirements

 After further consideration, the EPA believes the most 

appropriate approach to achieve the placement of monitors near 

non-inventoried sources that have the potential to cause an 

exceedance of the NAAQS is through the existing source-oriented 

monitoring network requirements (paragraph 4.5(a) of Appendix D 

to 40 CFR part 58) which require monitoring agencies to conduct 

lead monitoring at sources “which are expected to or have been 

Deleted: Pb

Deleted: Pb

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Deleted: Pb
27 

shown to contribute to a maximum lead concentration in ambient 

air in excess of the NAAQS” and the EPA Regional Administrators’ 

authority to require monitoring “where the likelihood of lead

air quality violations is significant.” These non-inventoried 

lead sources may be identified by monitoring agencies, the EPA, 

or concerned citizens as part of the network plan review and 

approval requirements. Furthermore, monitors sited under the 

source-oriented monitoring requirements are required to be sited 

at the location of estimated maximum concentration and, as such, 

better serve the purpose of identifying violations of the lead

NAAQS. 

The EPA believes it is appropriate to re-emphasize the 

objectives identified in the prior proposed rule for non-sourceoriented monitors, i.e., measuring typical neighborhood-scale 

lead concentrations in urban areas so we can better understand 

the risk posed by lead to the general population, and to provide 

information that could assist with the determination of 

nonattainment boundaries. In addition, the EPA believes nonsource-oriented sites are important to support the development 

of long-term trends at typical concentrations sites. 

The EPA notes that these objectives match those of the 

multi-pollutant NCore network required under section 3 of 

Appendix D to 40 CFR part 58 and also believes that EPA’s 

increasing support for multi-pollutant measurements should be 

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28 

considered in the design of the lead network. The NCore network 

is intended to be a long-term, multi-pollutant, monitoring 

network that not only provides information useful to NAAQS 

attainment decisions, but also provides data needed to broaden 

the understanding of air quality conditions and pollutant 

interactions, evaluate air quality models, develop emission 

control strategies, and support long-term health studies. We 

also note that lead monitoring is already required in at least 

one NCore site per EPA Region. As such, one option for 

implementing lead non-source-oriented monitoring is to require 

lead monitoring at all NCore sites rather than the populationbased approach currently used. This option provides a similar 

result to that of basing the non-source-oriented monitoring 

requirements on population (as was established in the November 

2008 final rule) and has additional similarities with the 

provisions adopted in the final rule on the revised lead NAAQS 

including: 

• The size of the network would be approximately the same as 

the original proposal but would span a wider range of 

populations. The NCore network will consist of 

approximately 80 sites, with approximately 50 of these 

being in urban areas with a population of 500,000 people or 

more. 

• NCore sites will be neighborhood-scale sites. 

Formatted: Bulleted + Level: 1 +

Aligned at: 0.25" + Tab after: 0.5"

+ Indent at: 0.5"

Formatted: Bulleted + Level: 1 +

Aligned at: 0.25" + Tab after: 0.5"

+ Indent at: 0.5"

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Deleted: to provide 

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29 

• NCore sites are long-term trends sites suitable for longterm population exposure studies. 

In addition, many NCore sites will have the low-volume PM10

sampler necessary to conduct lead monitoring, reducing the cost 

and time necessary to implement the non-source-oriented 

monitoring requirements.7 Additional information on the 

objectives and specific sites for NCore can be obtained online 

at http://www.epa.gov/ttn/amtic/ncore/index.html. Due to the 

many advantages of including lead monitoring at NCore sites 

rather than having separate non-source-oriented monitoring 

requirements, the EPA is proposing to revise the existing nonsource-oriented monitoring requirements (paragraph 4.5(b) of 

Appendix D to 40 CFR part 58) to require lead monitoring at all 

NCore sites in place of the current CBSA population-based 

requirements. The EPA seeks comments on the use of the NCore 

network to meet the non-source-oriented monitoring objectives 

for lead. The EPA also seeks comments on whether lead

monitoring should be required at all NCore sites, or only NCore 

sites in large urban areas (e.g., in CBSAs with a population 

greater than 500,000 people). 

 

7 EPA expects that low-volume PM10 samplers will be used at many NCore sites in 

order to meet the existing requirement for PM10-2.5 measurements. However, EPA 

notes that some NCore sites may use a dichotomous sampler or a continuous 

PM10-2.5 sampler that would not be compatible with lead-PM10 sampling such that 

these sites would need to add an additional low-volume PM10 sampler to perform 

lead-PM10 sampling. In addition, if lead-PM10 concentrations are found to be 

greater than 0.10 μg/m3, a lead-TSP sampler would be required at the NCore 

site according to paragraph 2.10.1.1 of Appendix C to 40 CFR part 58, within 

6 months. 

Formatted: Bulleted + Level: 1 +

Aligned at: 0.25" + Tab after: 0.5"

+ Indent at: 0.5"

Deleted: Pb

Deleted: Pb

Deleted: Pb

Deleted: Pb.

Deleted: if Pb

Deleted: urban 

Deleted: Pb

Deleted: Pb

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Deleted: Pb
30 

The EPA is also proposing to make a minor edit to the 

existing monitoring requirements. Paragraph 3(c) of Appendix D 

to 40 CFR part 58 requires lead monitoring at 10 NCore sites, 

located in the most populated MSA/CSA in each of the 10 EPA 

Regions. This requirement was added prior to the recent lead

monitoring revisions and was intended to provide for measurement 

of long-term lead trends away from lead sources. Since lead

monitoring would be required at all NCore sites if this proposal 

is finalized, paragraph 3(c) of Appendix D to 40 CFR part 58 is 

redundant and, as such, the EPA proposes to delete this 

paragraph.

VI. Increase in Lead Monitors and Timeline for Deploying New 

Monitors 

These proposed revisions to the monitoring requirements 

will result in an increase in the number of lead monitors that 

monitoring agencies must deploy and operate relative to the 

estimated number of monitors for the November 2008 final rule. 

Based on the 2005 NEI and the 2002 estimates for lead emissions 

from airports (EPA, 2008a), the current monitoring requirements 

would require up to 212 lead monitors - 111 source-oriented 

monitors8 (106 industrial and 5 airport) and 101 non-sourceoriented monitors. Based on the monitoring requirements 

 

8 Note that the current estimate of the required source-oriented sites is 

lower than the estimate identified in the final rule (135 sites) because the 

current estimate is based on the 2005 NEI rather than the 2002 NEI. 

Deleted: V

Deleted: Pb

Deleted: Pb

Deleted: Pb
31 

proposed here, the number of total required monitors increases 

to 352 monitors with 272 source-oriented monitors (217 

industrial and 55 airport) and 80 non-source-oriented monitors. 

However, we expect that the number of actual lead monitors will 

likely be less than 352 since these numbers do not take into 

account the probability that monitoring agencies will request 

and attain waivers from source-oriented monitoring requirements 

for some of the lead sources identified as emitting more than 

0.50 tpy of lead. 

 This proposal does not change the current requirement for

monitoring agencies to have lead monitors installed and 

operating near sources emitting 1.0 tpy of lead or more by 

January 1, 2010 (i.e., the deadline specified in the November 

2008 final rule). The EPA proposes that if we revise the 

monitoring requirements, monitoring agencies would have 6 months 

from the effective date of the final rule to update their annual 

monitoring network plans. The update would incorporate plans 

for source-oriented monitors near lead sources emitting 0.50 tpy 

or more, but less than 1.0 tpy. The EPA is also proposing to 

allow 1 year from the date of the final rule for monitoring 

agencies to install and begin operation of source-oriented 

monitors near lead sources emitting 0.50 tpy or more, but less 

than 1.0 tpy. 

Deleted: Pb

Deleted: values

Deleted: Pb

Deleted: Pb

Deleted: still requires

Deleted: Pb

Deleted: Pb

Deleted: Pb

Deleted: Pb
32 

The EPA notes that the timeline described above would 

require monitoring agencies to evaluate, site, and install up to 

161 source-oriented monitoring sites within 1 year of 

promulgation of the revised monitoring requirements. While the 

EPA believes this is feasible, the EPA seeks comments on the 

appropriateness of allowing deployment in phases requiring half 

of the sites for sources between 0.50 and 1.0 tpy to be 

installed during the first year following promulgation of the 

final monitoring requirements, and for the remaining half to be 

installed during the second year following promulgation of the 

final monitoring requirements. The EPA solicits comments on 

what factors should be considered when prioritizing which sites 

should be installed during the first year versus the second. 

The EPA specifically solicits comments on an alternative 

deployment schedule that would allow for monitors near airports 

to be deployed over 2 years, and on what factors should be 

considered when prioritizing airports to receive monitors in the 

first year of deployment.

 Monitoring agencies must have installed and begun operation 

of required NCore sites and monitors (other than lead) by 

January 1, 2011. Because the necessary siting and site 

installation will already be in place at NCore sites, the EPA 

does not believe any additional time beyond that of the existing 

NCore schedule is required for monitoring agencies to install 

Formatted: Indent: First line: 0.5"

Deleted: this 

Deleted: also 

Deleted: , such as source 

category,

Deleted: Pb
33 

any necessary lead monitors and begin lead sampling at NCore 

sites. As such, the EPA is proposing to require monitoring 

agencies to commence lead sampling at NCore sites when NCore 

sites are to become operational, no later than January 1, 2011. 

The EPA recognizes that these proposed requirements will 

not be finalized until spring 2010 at the earliest which is just 

a few months before monitoring agencies are currently required 

to submit their lead network plans for non-source-oriented 

monitors (July 1, 2010). Because this reconsideration may 

affect where non-source-oriented monitors may be required, the 

EPA is advising monitoring agencies to not site or install nonsource-oriented monitors until after this reconsideration is 

complete and the final revisions are promulgated. 

VII. Statutory and Executive Order Reviews 

A. Executive Order 12866: Regulatory Planning and Review

Under Executive Order 12866 (58 FR 51735, October 4, 1993), 

this action is a "significant regulatory action” because it was 

deemed to “raise novel legal or policy issues.” Accordingly, 

EPA submitted this action to the Office of Management and Budget 

(OMB) for review under Executive Order 12866 and any changes 

made in response to OMB recommendations have been documented in 

the docket for this action. 

B. Paperwork Reduction Act

Deleted: Pb

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Deleted: Pb

Deleted: be implemented

Deleted: likely 

Deleted: Pb
34 

The information collection requirements in this proposed 

rule have been submitted for approval to OMB under the Paperwork 

Reduction Act, 44 U.S.C. 3501 et seq. The Information 

Collection Request (ICR) document prepared by EPA has been 

assigned EPA ICR number 2378.01. 

The monitoring, recordkeeping, and reporting requirements 

in 40 CFR parts 58 are specifically authorized by sections 100, 

301(a), and 319 of the Clean Air Act (CAA). All information 

submitted to EPA pursuant to the monitoring, recordkeeping, and 

reporting requirements for which a claim of confidentiality is 

made is safeguarded according to Agency policies in 40 CFR part 

2, subpart B. 

 The information collected and reported under 40 CFR part 58 

is needed to determine compliance with the NAAQS, to 

characterize air quality and associated health and ecosystem 

impacts, to develop emissions control strategies, and to measure 

progress for the air pollution program. The proposed amendments 

would revise the technical requirements for lead monitoring 

sites, require the siting and operation of additional lead

ambient air monitors, and require the reporting of the collected 

ambient lead monitoring data to EPA’s AQS. The annual average 

reporting burden for the collection under 40 CFR part 58 

(averaged over the first 3 years of this ICR) for 105

respondents is estimated to increase by a total of 19,551 labor 

Deleted: 0940.23

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Deleted: Pb

Deleted: Pb

Deleted: 140
35 

hours per year with an increase of $1,849,264 per year. Burden 

is defined at 5 CFR 1320.3(b). State, local, and Tribal 

entities are eligible for state assistance grants provided by 

the federal government under the CAA which can be used for 

monitors and related activities. 

An agency may not conduct or sponsor, and a person is not 

required to respond to, a collection of information unless it 

displays a currently valid OMB control number. The OMB control 

numbers for EPA's regulations in 40 CFR are listed in 40 CFR 

part 9. 

 To comment on the Agency's need for this information, the 

accuracy of the provided burden estimates, and any suggested 

methods for minimizing respondent burden, EPA has established a 

public docket for this rule, which includes this ICR, under 

Docket ID number EPA-HQ-OAR-2006-0735. Submit any comments 

related to the ICR to EPA and OMB. See ADDRESSES section at the 

beginning of this notice for where to submit comments to EPA. 

Send comments to OMB at the Office of Information and Regulatory 

Affairs, Office of Management and Budget, 725 17th Street, NW, 

Washington, DC 20503, Attention: Desk Office for EPA. Since OMB 

is required to make a decision concerning the ICR between 30 and 

60 days after [Insert date of publication in the Federal

Register], a comment to OMB is best assured of having its full 

effect if OMB receives it by [Insert date 30 days after 
36 

publication in the Federal Register.]. The final rule will 

respond to any OMB or public comments on the information 

collection requirements contained in this proposal. 

C. Regulatory Flexibility Act

 The Regulatory Flexibility Act (RFA) generally requires an 

agency to prepare a regulatory flexibility analysis of any rule 

subject to notice and comment rulemaking requirements under the 

Administrative Procedure Act or any other statute unless the 

agency certifies that the rule will not have a significant 

economic impact on a substantial number of small entities. 

Small entities include small businesses, small organizations, 

and small governmental jurisdictions. 

 For purposes of assessing the impacts of this rule on small 

entities, small entity is defined as: (1) a small business as 

defined by the Small Business Administration’s (SBA) regulations 

at 13 CFR 121.201; (2) a small governmental jurisdiction that is 

a government of a city, county, town, school district, or 

special district with a population of less than 50,000; and (3) 

a small organization that is any not-for-profit enterprise which 

is independently owned and operated and is not dominant in its 

field. 

 After considering the economic impacts of this proposed 

rule on small entities, I certify that this action will not have 

a significant economic impact on a substantial number of small 

Deleted: 
37 

entities. This proposed rule will not impose any requirements 

on small entities. Rather, this rule establishes monitoring 

requirements for state and local (where applicable) monitoring 

agencies. The EPA continues to be interested in the potential 

impacts of the proposed rule on small entities and welcomes 

comments on issues related to such impacts. 

D. Unfunded Mandates Reform Act (UMRA) 

 This rule does not contain a federal mandate that may 

result in expenditures of $100 million or more for state, local, 

and Tribal governments, in the aggregate, or the private sector 

in any 1 year. The proposed amendments to 40 CFR part 58 are 

estimated to increase the ambient air monitoring costs by $1.8 

million and 19,551 labor hours from present levels. Thus, this 

rule is not subject to the requirements of sections 202 or 205 

of UMRA. 

This rule is also not subject to the requirements of 

section 203 of UMRA because it contains no regulatory 

requirements that might significantly or uniquely affect small 

governments. Small governments that may be affected by the 

proposed amendments are already meeting similar requirements 

under the existing rules, and the costs of changing the network 

design requirements would be borne, in part, by the federal 

government through state assistance grants.
38 

E. Executive Order 13132: Federalism

 Executive Order 13132, entitled “Federalism” (64 FR 43255, 

August 10, 1999), requires EPA to develop an accountable process 

to ensure “meaningful and timely input by state and local 

officials in the development of regulatory policies that have 

federalism implications.” “Policies that have federalism 

implications” are defined in the Executive Order to include 

regulations that have “substantial direct effects on the states, 

on the relationship between the national government and the 

states, or on the distribution of power and responsibilities 

among the various levels of government.” 

 This proposed rule does not have federalism implications. 

It will not have substantial direct effects on the states, on 

the relationship between the national government and the states, 

or on the distribution of power and responsibilities among the 

various levels of government, as specified in Executive Order 

13132. The rule does not alter the relationship between the 

federal government and the states regarding the establishment 

and implementation of air quality improvement programs as 

codified in the CAA. Under section 109 of the CAA, EPA is 

mandated to establish NAAQS; however, CAA section 116 preserves 

the rights of states to establish more stringent requirements if 

deemed necessary by a state. Furthermore, this rule does not 

impact CAA section 107 which establishes that the states have 

Deleted: Federal
39 

primary responsibility for implementation of the NAAQS. 

Finally, as noted in section D (above) on UMRA, this rule does 

not impose significant costs on state, local, or Tribal 

governments or the private sector. Thus, Executive Order 13132 

does not apply to this rule. 

However, EPA recognizes that states will have a substantial 

interest in this rule and any corresponding revisions to 

associated air quality surveillance requirements, 40 CFR part 

58. Therefore, in the spirit of Executive Order 13132, and 

consistent with EPA policy to promote communications between EPA 

and state and local governments, EPA specifically solicits 

comment on this proposed rule from state and local officials. 

F. Executive Order 13175: Consultation and Coordination

With Indian Tribal Governments

 This action does not have Tribal implications, as specified 

in Executive Order 13175 (65 FR 67249, November 9, 2000). It 

does not have a substantial direct effect on one or more Indian 

Tribes, since Tribes are not obligated to adopt or implement any 

NAAQS. Thus, Executive Order 13175 does not apply to this 

action. EPA specifically solicits additional comment on this 

proposed action from Tribal officials. 
40 

G. Executive Order 13045: Protection of Children From 

Environmental Health & Safety Risks

 The EPA interprets Executive Order 13045 (62 FR 19885, 

April 23, 1997) as applying only to those regulatory actions 

that concern health or safety risks, such that the analysis 

required under section 5-501 of the Executive Order has the 

potential to influence the regulation. This action is not 

subject to Executive Order 13045 because it does not establish 

an environmental standard intended to mitigate health or safety 

risks. 

H. Executive Order 13211: Actions That Significantly Affect 

Energy Supply, Distribution, or Use

 This action is not a “significant energy action” as defined 

in Executive Order 13211 (66 FR 28355 (May 22, 2001)), because 

it is not likely to have a significant adverse effect on the 

supply, distribution, or use of energy. This proposed rule 

would result in an insignificant increase in power consumption 

associated with the additional power required to run 140 

additional monitors nationwide. 

I. National Technology Transfer and Advancement Act

 Section 12(d) of the National Technology Transfer and 

Advancement Act of 1995 (“NTTAA”), Public Law No. 104-113, 12(d) 

(15 U.S.C. 272 note) directs EPA to use voluntary consensus 

standards in its regulatory activities unless to do so would be 
41 

inconsistent with applicable law or otherwise impractical. 

Voluntary consensus standards are technical standards (e.g., 

materials specifications, test methods, sampling procedures, and 

business practices) that are developed or adopted by voluntary 

consensus standards bodies. NTTAA directs EPA to provide 

Congress, through OMB, explanations when the Agency decides not 

to use available and applicable voluntary consensus standards. 

 This proposed rulemaking does not involve technical 

standards. Therefore, EPA is not considering the use of any 

voluntary consensus standards.

J. Executive Order 12898: Federal Actions to Address

Environmental Justice in Minority Populations and

Low-Income Populations

 Executive Order 12898 (59 FR 7629 (Feb. 16, 1994))

establishes federal executive policy on environmental justice. 

Its main provision directs federal agencies, to the greatest 

extent practicable and permitted by law, to make environmental 

justice part of their mission by identifying and addressing, as 

appropriate, disproportionately high and adverse human health or 

environmental effects of their programs, policies, and 

activities on minority populations and low-income populations in 

the United States. 

 The EPA has determined that this proposed rule will not 

have disproportionately high and adverse human health or 
42 

environmental effects on minority or low-income populations 

because it increases the level of environmental protection for 

all affected populations without having any disproportionately 

high and adverse human health or environmental effects on any 

population, including any minority or low-income population. 

VIII. References 

Cavender, K. (2008). Development of Final Source-oriented 

Monitoring Emission Threshold. Memorandum to the Lead 

NAAQS Review Docket. EPA-HQ-OAR-2006-0735. Available 

online at: 

http://www.epa.gov/ttnnaaqs/standards/lead/data/20081015Cav

ender.pdf 

Cavender, K. (2009a). Summary of Discussion of Lead Monitoring 

Near Airports at Spring 2009 NACAA Monitoring Subcommittee 

Meeting. Memorandum to the Lead NAAQS Review Docket. EPAHQ-OAR-2006-0735.

Cavender, K. (2009b). Review of Pb Monitoring Conducted Near 

General Aviation Airports. Memorandum to the Lead NAAQS 

Review Docket. EPA-HQ-OAR-2006-0735. 

Fine, Philip (2007). Community-Scale Air Toxics Monitoring - 

Sun Valley Neighborhood and General Aviation Airports. 

Presented at the U.S. EPA Air Toxics Data Analysis Workshop 

- Chicago, IL, October 2 - 4, 2007. EPA-HQ-OAR-2006-0735. 

Deleted: pb

Deleted: Pb
43 

Available online at: 

http://www.epa.gov/ttn/amtic/files/ambient/airtox/2007-

workshop/07_100307_fine.pdf 

Jackson, L. (2009). Letter to petitioners. EPA-HQ-OAR-2006-

0735. Available online at: 

http://www.epa.gov/air/lead/pdfs/OAR.09.000.7687.pdf 

NRDC, et al. (2009). Petition to Reconsider. EPA-HQ-OAR-2006-

0735. Available online at: 

http://www.epa.gov/air/lead/pdfs/0122009petitionReconsidera

tion.pdf 

U.S. Environmental Protection Agency. (2006) Air Quality 

Criteria for Lead (Second External Review Draft). 

Washington, DC, EPA/600/R–05/144aB–bB. Available online at: 

http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=158823 

U.S. Environmental Protection Agency. (2008a) Lead Emissions 

from the Use of Leaded Aviation Gasoline in the United 

States. EPA420-R-08-020. Available online at: 

http://www.epa.gov/ttn/chief/net/tsd_avgas_lead_inventory_2

002.pdf

U.S. Environmental Protection Agency. (2008b) Regulatory Impact 

Analysis of the Proposed Revisions to the National Ambient 

Air Quality Standards for Lead. EPA-HQ-OAR-2006-0735. 

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Page 45 of 49

Revisions to Lead Ambient Air Monitoring Requirements 

List of Subjects in 40 CFR Part 58 

Air pollution control, Environmental protection, 

Intergovernmental relations, Reporting and Recordkeeping 

Requirements. 

 ____________________ 

 Dated: 

____________________ 

Lisa P. Jackson, 

 Administrator. 

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Deleted: 41
46 

For the reasons stated in the preamble, title 40, chapter I, 

part 58 of the Code of Federal Regulations is proposed to be 

amended as follows: 

PART 58—[AMENDED] 

1. The authority citation for part 58 continues to read as 

follows: 

Authority: 42 U.S.C. 7403, 7410, 7601(a), 7611, and 7619. 

Subpart B—[Amended] 

2. Section 58.10, is amended by revising paragraph (a)(4) to 

read as follows: 

§ 58.10 Annual monitoring network plan and periodic network 

assessment. 

 (a) * * * 

 (4) A plan for establishing source-oriented lead monitoring 

sites in accordance with the requirements of appendix D to this 

part for lead sources emitting 1.0 tpy or greater shall be 

submitted to the EPA Regional Administrator no later than July 

1, 2009, as part of the annual network plan required in 

paragraph (a)(1) of this section. The plan shall provide for 

the required source-oriented lead monitoring sites for lead

sources emitting 1.0 tpy or greater to be operational by January 

1, 2010. A plan for establishing source-oriented lead

monitoring sites in accordance with the requirements of appendix 

D to this part for lead sources emitting greater than 0.50 tpy 

Formatted

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47 

but less than 1.0 tpy shall be submitted to the EPA Regional 

Administrator no later than [insert date 6 months after date of 

publication of the final rule in the Federal Register]. The 

plan shall provide for the required source-oriented lead

monitoring sites for lead sources emitting greater than 0.50 tpy 

but less than 1.0 tpy to be operational by [insert date 12 

months after date of publication of the final rule in the 

Federal Register]. 

* * * * * 

3. Appendix D to Part 58 is amended as follows: 

 a. By revising paragraph 3.(b),

 b. By removing and reserving paragraph 3.(c),

 c. By revising 4.5.(a), and

 d. By revising paragraph 4.5.(b).

Appendix D to Part 58—Network Design Criteria for Ambient Air 

Quality Monitoring 

 * * * * * 

 3. * * * 

 (b) The NCore sites must measure, at a minimum, PM2.5

particle mass using continuous and integrated/filter-based 

samplers, speciated PM2.5, PM10–2.5 particle mass, speciated PM10–

2.5, O3, SO2, CO, NO/NOy, lead, wind speed, wind direction, 

relative humidity, and ambient temperature. 

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Deleted: ) to read as 

follows:

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48 

 (c) [Reserved.]

 * * * * * 

 4.5 * * * (a) State and, where appropriate, local agencies 

are required to conduct ambient air lead monitoring near lead

sources which are expected to or have been shown to contribute 

to a maximum lead concentration in ambient air in excess of the 

NAAQS, taking into account the logistics and potential for 

population exposure. At a minimum, there must be one sourceoriented SLAMS site located to measure the maximum lead

concentration in ambient air resulting from each lead source 

which emits 0.50 or more tons per year based on either the most 

recent National Emission Inventory 

(http://www.epa.gov/ttn/chief/eiinformation.html) or other 

scientifically justifiable methods and data (such as improved 

emissions factors or site-specific data) taking into account 

logistics and the potential for population exposure. 

 (i) One monitor may be used to meet the requirement in 

paragraph 4.5(a) for all sources involved when the location of 

the maximum lead concentration due to one lead source is 

expected to also be impacted by lead emissions from a nearby 

source (or multiple sources). This monitor must be sited, 

taking into account logistics and the potential for population 

exposure, where the lead concentration from all sources combined 

is expected to be at its maximum. 

Deleted: Lead (Pb) Design 

Criteria.

Deleted: state

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Deleted: 

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49 

 (ii) The Regional Administrator may waive the requirement 

in paragraph 4.5(a) for monitoring near lead sources if the 

state or, where appropriate, local agency can demonstrate the 

lead source will not contribute to a maximum lead concentration 

in ambient air in excess of 50 percent of the NAAQS (based on 

historical monitoring data, modeling, or other means). The 

waiver must be renewed once every 5 years as part of the network 

assessment required under §58.10(d). 

 (b) State and, where appropriate, local agencies are 

required to conduct non-source-oriented lead monitoring at each 

NCore site required under paragraph 3 of this appendix. 

 * * * * * 

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