31306 Federal Register / Vol. 75, No. 106 / Thursday, June 3, 2010 / Rules and Regulations 

Name of nonregulatory 

SIP provision 

Applicable 

geographic or 

non-attainment 

area 

State submittal date/ 

adopted date 

EPA approval date and 

citation 3 Explanations 

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

2. Legal Authority 

3. Control Strategy 

4. Compliance Schedule 

5. Prevention of Air Pollution 

Emergency Episodes 

7. Review of New Sources and 

Modifications 

8. Source Surveillance 

9. Resources 

......................... Clarification submitted: 

6/14/73 

2/19/74 

6/26/74 

11/21/74 

4/23/75. 

With all clarifications: 

3/2/76, 41 FR 8956. 

10. Inter-governmental Cooperation 

11. Rules and Regulations 

With subsequent revisions to 

the chapters as follows: 

* * * * * * * 

(21) Section 7.8, Interstate Transport of Air Pollution (only 7.8.1.A., 

portions of 7.8.1.B., and 7.8.1.C., 

see explanation.) 

Statewide ........ Submitted: 4/09/09 

Adopted: 4/01/09. 

6/3/10 75 FR 31290 ........... Includes Section 7.8, subsection Portions of 7.8.1 

as indicated below: 

7.8.1.A, ‘‘Overview,’’ the 

language of Subsection 

7.8.1.B., ‘‘Nonattainment 

and Maintenance Area 

Impact,’’ that specifically 

addresses the ‘‘significant 

contribution to nonattainment’’ requirement of 

CAA Section 

110(a)(2)(D)(i), and all of 

7.8.1.C. 

3 In order to determine the EPA effective date for a specific provision listed in this table, consult the Federal Register notice cited in this column for the particular provision. 

[FR Doc. 2010–13051 Filed 6–2–10; 8:45 am] 

BILLING CODE 6560–50–P 

ENVIRONMENTAL PROTECTION 

AGENCY 

40 CFR Part 52 

[EPA–R08–OAR–2007–1032; FRL–9155–5] 

Approval and Promulgation of State 

Implementation Plans; State of 

Colorado; Interstate Transport of 

Pollution Revisions for the 1997 8-hour 

Ozone NAAQS: ‘‘Significant 

Contribution to Nonattainment’’ 

Requirement 

AGENCY: Environmental Protection 

Agency (EPA). 

ACTION: Final rule. 

SUMMARY: EPA is partially approving 

State Implementation Plan (SIP) 

revisions submitted by the State of 

Colorado on June 18, 2009. These 

revisions, referred to as the Colorado 

Interstate Transport SIP, address the 

requirements of Clean Air Act section 

110(a)(2)(D)(i)(I) for the 1997 8-hour 

ozone National Ambient Air Quality 

Standards (NAAQS). In this action EPA 

is approving the Colorado Interstate 

Transport SIP non-regulatory provisions 

that address the requirement of section 

110(a)(2)(D)(i)(I) that emissions from the 

state’s sources do not ‘‘contribute 

significantly’’ to nonattainment of the 

1997 8-hour ozone NAAQS in any other 

state. EPA will act at a later date on the 

Colorado Interstate Transport SIP 

provisions that address the requirement 

of section 110(a)(2)(D)(i)(I) that 

emissions from the state’s sources do 

not ‘‘interfere with maintenance’’ of the 

1997 8-hour ozone NAAQS in any other 

state. This action is being taken under 

section 110 of the Clean Air Act. 

DATES: Effective Date: This final rule is 

effective July 6, 2010. 

ADDRESSES: EPA has established a 

docket for this action under Docket ID 

No. EPA–R08–OAR–2007–1032. All 

documents in the docket are listed on 

the http://www.regulations.gov Web 

site. Although listed in the index, some 

information is not publicly available, 

e.g., Confidential Business Information 

(CBI) or other information whose 

disclosure is restricted by statute. 

Certain other material, such as 

copyrighted material, is not placed on 

the Internet and will be publicly 

available only in hard copy form. 

Publicly available docket materials are 

available either electronically through 

http://www.regulations.gov, or in hard 

copy at the Air Program, Environmental 

Protection Agency (EPA), Region 8, 

1595 Wynkoop Street, Denver, Colorado 

80202–1129. EPA requests that if at all 

possible, you contact the individual 

listed in the FOR FURTHER INFORMATION

CONTACT section to view the hard copy 

of the docket. You may view the hard 

copy of the docket Monday through 

Friday, 8:00 a.m. to 4:00 p.m., excluding 

Federal holidays. 

FOR FURTHER INFORMATION CONTACT: 

Domenico Mastrangelo, Air Program, 

U.S. Environmental Protection Agency, 

Region 8, Mailcode 8P–AR, 1595 

Wynkoop Street, Denver, Colorado 

80202–1129, (303) 312–6416, 

mastrangelo.domenico@epa.gov. 

SUPPLEMENTARY INFORMATION: 

Definitions 

For the purpose of this document, we 

are giving meaning to certain words or 

initials as follows: 

(i) The words or initials Act or CAA 

mean or refer to the Clean Air Act, 

unless the context indicates otherwise. 


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Federal Register / Vol. 75, No. 106 / Thursday, June 3, 2010 / Rules and Regulations 31307 

1 In this action the expression ‘‘CAIR’’ refers to the 

final rule published in the May 12, 2005 Federal 

Register and entitled ‘‘Rule to Reduce Interstate 

Transport of Fine Particulate Matter and Ozone 

(Clean Air Interstate Rule); Revisions to Acid Rain 

Program; Revisions to NOX SIP Call; Final Rule’’ (70 

FR 25162). 

(ii) The words EPA, we, us or our 

mean or refer to the United States 

Environmental Protection Agency. 

(iii) The initials SIP mean or refer to 

State Implementation Plan. 

(iv) The words State or Colorado 

mean the State of Colorado, unless the 

context indicates otherwise. 

Table of Contents 

I. Background 

II. Response to Comments 

III. Section 110(l) 

IV. Final Action 

V. Statutory and Executive Order Reviews 

I. Background 

Section 110(a)(2)(D)(i) of the CAA 

requires that a state’s SIP must contain 

adequate provisions prohibiting any 

source or other type of emissions 

activity within the state from emitting 

any air pollutant in amounts which will: 

(1) Contribute significantly to 

nonattainment of the NAAQS in any 

other state; (2) interfere with 

maintenance of the NAAQS by any 

other state; (3) interfere with any other 

state’s required measures to prevent 

significant deterioration of air quality; 

or (4) interfere with any other state’s 

required measures to protect visibility. 

On March 31, 2010, EPA published a 

notice of proposed rulemaking (NPR) 

proposing partial approval of the State 

Implementation Plan (SIP) revision 

‘‘State of Colorado Implementation Plan 

to Meet the Requirements of Clean Air 

Act Section 110(a)(2)(D)(i)(I)—Interstate 

Transport Regarding the 1997 8-Hour 

Ozone Standard,’’ submitted by the State 

on June 18, 2009. As indicated by the 

title, this SIP addresses the first two of 

the four requirements listed above-i.e., 

(1), ‘‘significant contribution,’’ and (2), 

‘‘interference with maintenance.’’ EPA’s 

proposed rule action reviewed and 

proposed approval of the Colorado SIP’s 

section addressing only the ‘‘significant 

contribution’’ requirement. EPA will act 

at a later date on the Colorado Interstate 

Transport SIP section that addresses the 

‘‘interference with maintenance’’ 

requirement. 

To assess whether emissions from 

Colorado contribute significantly to 

downwind nonattainment for the 1997 

8-hour ozone NAAQS, EPA’s technical 

analysis relied on EPA’s 2006 Guidance, 

recommending consideration of 

available EPA modeling conducted in 

conjunction with CAIR,1 or in the 

absence of such EPA modeling, 

consideration of other information such 

as the amount of emissions, the 

geographic location of violating areas, 

meteorological data, or various other 

forms of information that would be 

relevant to assessing the likelihood of 

significant contribution to violations of 

the NAAQS in another state. Consistent 

with the NOX SIP Call and CAIR, our 

technical analysis assessed the extent of 

ozone transport from Colorado not just 

to areas designated nonattainment, but 

also to areas in violation of the NAAQS. 

Because EPA did not have detailed 

modeling for Colorado and nearby 

downwind states, our approach did not 

rely on a quantitative determination of 

Colorado’s contribution but on a weightof-evidence approach using quantitative 

information such as Colorado’s distance 

from areas with monitors showing 

violations of the NAAQS, modeling 

results outlining wind vectors for 

regional transport of ozone on high 

ozone days, back trajectory analyses for 

the downwind nonattainment areas 

closest to the State, and results of 

modeling studies for the nonattainment 

areas specifying the range of wind 

directions along which contribution of 

ozone transport occurred. Given that the 

assessments for each of these pieces of 

evidence are not individually definitive 

or outcome determinative, EPA 

concluded in its proposed action that 

the various factual and technical 

considerations supported a 

determination of no significant 

contribution from Colorado emissions to 

the ozone nonattainment areas noted 

above. EPA did not receive comments 

that persuade the Agency that there is 

such significant contribution, and thus 

in today’s final action EPA is making a 

final regulatory determination that 

Colorado emissions sources do not 

contribute significantly to violations of 

the 1997 8-hour ozone NAAQS in any 

other state. 

II. Response to Comments 

EPA received one letter from 

WildEarth Guardians (WG) commenting 

on EPA’s Federal Register action 

proposing approval of the portion of the 

Colorado Interstate Transport SIP that 

addresses the ‘‘significant contribution 

to nonattainment’’ requirement of CAA 

Section 110(a)(2)(D)(i)(I) for the 1997 8- 

hour ozone NAAQS. In this section EPA 

responds to the significant adverse 

comments made by the commenter. 

Comment No. 1—The commenter 

asserted that EPA’s proposed approval 

was based on a ‘‘flawed legal standard.’’ 

According to the commenter, EPA erred 

in the proposal by explaining that 

various factual or technical assessments 

indicate that it is ‘‘unlikely’’ that 

emissions from Colorado sources 

significantly contribute to violations of 

the 8-hour ozone NAAQS in other 

states. The commenter’s position was 

that EPA cannot approve a SIP 

submission based upon ‘‘unlikelihood’’ 

because CAA Section 110(a)(2)(D)(i)(I) 

prohibits emissions that contribute 

significantly to nonattainment in other 

States and does not allow EPA to 

approve SIPs simply because a state’s 

emissions are ‘‘unlikely’’ to contribute 

significantly to nonattainment. 

EPA Response—EPA disagrees with 

the commenter’s characterization of 

EPA’s analysis and the commenter’s 

interpretation of the statutory 

requirements. First, EPA notes that the 

discussion in the proposal was intended 

to present the various factual and 

technical considerations available to 

assess whether there is or is not 

significant contribution to 

nonattainment in other states as a result 

of emissions from Colorado sources. 

Given that these assessments are not 

individually definitive or outcome 

determinative, EPA believes that it is 

entirely appropriate to present and 

describe the relative probative value of 

the various considerations accurately. 

Second, EPA notes that all such 

technical evaluations are by their nature 

subject to some degree of uncertainty. 

Indeed, the modeling that the 

commenter elsewhere contends should 

be the sole method for evaluating 

interstate transport is itself but one 

means of evaluating the real world 

impacts of emissions in light of 

meteorological conditions, wind 

direction, and other such variables and 

produces a result that is itself subject to 

some degree of uncertainty. Third, EPA 

believes that it was also appropriate to 

describe the various factual and 

technical considerations and whether 

they indicated a ‘‘likelihood’’ of 

significant contribution to 

nonattainment in another state because 

the proposal was seeking comment from 

the public upon whether these 

considerations together supported a 

determination of no such significant 

contribution. EPA did not receive 

comments that persuade the Agency 

that there is such significant 

contribution, and thus in today’s final 

action EPA is making a final regulatory 

determination that Colorado emissions 

sources do not significantly contribute 

to violations of the 1997 8-hour ozone 

NAAQS in any other state, for the 

reasons explained elsewhere in this 

notice. In other words, EPA has 

concluded that the existing SIP for 

Colorado already contains adequate 


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31308 Federal Register / Vol. 75, No. 106 / Thursday, June 3, 2010 / Rules and Regulations 

2Memorandum from William T. Harnett entitled 

Guidance for State Implementation Plan (SIP) 

Submissions to Meet Current Outstanding 

Obligations Under Section 110(a)(2)(D)(i) for the 8- 

hour Ozone and PM2.5 National Ambient Air 

Quality Standards (Aug. 15, 2006) (‘‘2006 

Guidance’’); p. 3. An electronic copy is available for 

review at the regulations.gov web site as Document 

ID No. EPA–R08–OAR–2007–1032.0004.1. 

3 Id. at 3. 

4 Id. 

5 In this action the expression ‘‘CAIR’’ refers to the 

final rule published in the May 12, 2005 Federal 

Register and entitled ‘‘Rule to Reduce Interstate 

Transport of Fine Particulate Matter and Ozone 

(Clean Air Interstate Rule); Revisions to Acid Rain 

Program; Revisions to NOX SIP Call; Final Rule’’ (70 

FR 25162). 6 Id. at 5. 

provisions to prevent emissions from 

Colorado sources from significantly 

contributing to violations of the 1997 8- 

hour ozone NAAQS in other states and 

is therefore approving Colorado’s 

submission for this purpose. 

Comment No. 2—The commenter 

argued that Colorado and EPA did not 

appropriately assess impacts to 

nonattainment in downwind states. 

According to the commenter, Colorado 

failed to assess significance of 

downwind impacts in accordance with 

EPA guidance and precedent. Although 

this is unclear from the comment, the 

commenter evidently believes that 

EPA’s applicable guidance for this 

purpose appears only in the 1998 NOX

SIP call. The commenter asserts that, 

based on the precedent of the NOX SIP 

Call, the following issues need to be 

addressed in determining whether or 

not an area is significantly contributing 

to nonattainment in downwind States: 

(a) The overall nature of the ozone 

problem; (b) the extent of downwind 

nonattainment problems to which 

upwind State’s emissions are linked; (c) 

the ambient impact of the emissions 

from upwind States’ sources on the 

downwind nonattainment problems; 

and (d) the availability of high costeffective control measures for upwind 

emissions. (63 FR 57356–57376, October 

27, 1998). 

EPA Response—EPA disagrees with 

the commenter on this point. Section 

110(a)(2)(D) does not explicitly specify 

how states or EPA should evaluate the 

existence of, or extent of, interstate 

transport and whether that interstate 

transport is of sufficient magnitude to 

constitute ‘‘significant contribution to 

nonattainment’’ as a regulatory matter. 

The statutory language is ambiguous on 

its face and EPA must reasonably 

interpret that language when it applies 

it to factual situations before the 

Agency. 

EPA agrees that the NOX SIP Call is 

one rulemaking in which EPA evaluated 

the existence of, and extent of, interstate 

transport. In that action, EPA developed 

an approach that allowed the Agency to 

evaluate whether there was significant 

contribution to ozone nonattainment 

across an entire region that was 

comprised of many states. That 

approach included regional scale 

modeling and other technical analyses 

that EPA deemed useful to evaluate the 

issue of interstate transport on that 

geographic scale and for the facts and 

circumstances at issue in that 

rulemaking. EPA does not agree, 

however, that the approach of the NOX

SIP Call is necessarily the only way that 

states or EPA may evaluate the existence 

of, and extent of, interstate transport in 

all situations, and especially in 

situations where the state and EPA are 

evaluating the question on a state by 

state basis, and in situations where there 

is not evidence of widespread interstate 

transport. 

Indeed, EPA issued specific guidance 

making recommendations to states 

about how to address section 

110(a)(2)(D) in SIP submissions for the 

8-hour ozone NAAQS. EPA issued this 

guidance document, entitled ‘‘Guidance 

for State Implementation Plan (SIP) 

Submissions to Meet Current 

Outstanding Obligations Under Section 

110(a)(2)(D)(i) for the 8-Hour Ozone and 

PM2.5 National Ambient Air Quality 

Standards’’ on August 15, 2006.2 This 

guidance document postdated the NOX

SIP Call, and was developed by EPA 

specifically to address SIP submissions 

for the 1997 8-hour ozone NAAQS. 

Within that 2006 guidance document, 

EPA notes that it explicitly stated its 

view that the ‘‘precise nature and 

contents of such a submission [are] not 

stipulated in the statute’’ and that the 

contents of the SIP submission ‘‘may 

vary depending upon the facts and 

circumstances related to the specific 

NAAQS.’’ 3 Moreover, within that 

guidance, EPA expressed its view that 

‘‘the data and analytical tools available’’ 

at the time of the SIP submission 

‘‘necessarily affect[] the content of the 

required submission.’’ 4 To that end, 

EPA specifically recommended that 

states located within the geographic 

region covered by the ‘‘Clean Air 

Interstate Rule’’ (CAIR) 5 comply with 

section 110(a)(2)(D) for the 1997 8-hour 

ozone NAAQS by complying with CAIR 

itself. For states outside the CAIR rule 

region, however, EPA recommended 

that states develop their SIP 

submissions for section 110(a)(2)(D) 

considering relevant information. 

EPA explicitly recommended that 

relevant information for section 

110(a)(2)(D) submissions addressing 

significant contribution to 

nonattainment ‘‘might include, but is 

not limited to, information concerning 

emissions in the State, meteorological 

conditions in the State, the distance to 

the nearest nonattainment area in 

another State, reliance on modeling 

conducted by EPA in determining that 

such State should not be included 

within the ambit of the CAIR, or such 

other information as the State considers 

probative on the issue of significant 

contribution.’’ 6 In addition, EPA 

recommended that states might elect to 

evaluate significant contribution to 

nonattainment using relevant 

considerations comparable to those used 

by EPA in CAIR, including evaluating 

impacts as of an appropriate year (such 

as 2010) and in light of the cost of 

control to mitigate emissions that 

resulted in interstate transport. 

The commenter did not acknowledge 

or discuss EPA’s actual guidance for 

section 110(a)(2)(D) SIP submissions for 

the 1997 8-hour ozone NAAQS, and 

thus it is unclear whether the 

commenter was aware of it. In any 

event, EPA believes that the Colorado 

submission and EPA’s evaluation of it 

was consistent with EPA’s guidance for 

the 1997 8-hour ozone NAAQS. For 

example, as discussed in the proposal 

notice, the state and EPA considered 

information such as monitoring data in 

Colorado and downwind states, 

geographical and meteorological 

information, and technical studies of the 

nature and sources of nonattainment 

problems in various downwind states. 

These are among the types of 

information that EPA recommended and 

that EPA considers relevant. Thus, EPA 

has concluded that the state’s 

submission, and EPA’s evaluation of 

that submission, meet the requirements 

of section 110(a)(2)(D) and are 

consistent with applicable guidance. 

Finally, EPA notes that the 

considerations the Agency 

recommended to states in the 2006 

guidance document are consistent with 

the concepts that the commenter 

enumerated from the NOX SIP Call 

context: (a) The overall nature of the 

ozone problem; (b) the extent of 

downwind nonattainment problems to 

which upwind State’s emissions are 

linked; (c) the ambient impact of the 

emissions from upwind States’ sources 

on the downwind nonattainment 

problems; and (d) the availability of 

high cost-effective control measures for 

upwind emissions. The only distinction 

in the case of the Colorado submission 

at issue here would be that because the 

available evidence indicates that there is 

very little contribution from emissions 

from Colorado sources to nonattainment 

in other states, it is not necessary to 


emcdonald on DSK2BSOYB1PROD with RULES
Federal Register / Vol. 75, No. 106 / Thursday, June 3, 2010 / Rules and Regulations 31309 

advance to the final step and evaluate 

whether the cost of controls for those 

sources is above or below a certain cost 

of control as part of determining 

whether the contribution constitutes 

‘‘significant contribution to 

nonattainment’’ for regulatory purposes, 

as was necessary in the NOX SIP Call 

and in CAIR. 

Comment No. 3—The commenter 

argued that Colorado based its claim of 

no significant contribution ‘‘primarily 

on attainment plan modeling for the 

Denver Metropolitan Area/North Front 

Range (DMA/NFR) nonattainment area’’ 

and noted that EPA itself ‘‘does not 

accept’’ that modeling for purposes of 

assessing impacts on nonattainment in 

downwind States. 

EPA Response—EPA disagrees with 

the commenter’s characterization of the 

state’s submission and of EPA’s 

evaluation of it. This comment reflects 

an incomplete reading of EPA’s 

evaluation of how the results of 

Colorado’s modeling analysis for the 

DMA/NFR relate to an assessment of 

whether emissions from Colorado 

sources contribute significantly to 

downwind nonattainment of the 1997 8- 

hour ozone NAAQS in other states. 

It is correct that the State relied upon 

this information in its submission to 

EPA. It is correct that EPA did not agree 

with Colorado’s view that the modeling 

analysis results for the DMA/NFR 

attainment plan, in and of themselves, 

prove that there could be no significant 

contribution from Colorado sources to 

downwind ozone nonattainment in 

other states. EPA explicitly disagreed 

with the state’s belief that: ‘‘ * * * these 

results [of the DMA/NFR modeling 

analysis] demonstrate that the 

magnitude of ozone transport from 

Colorado to other States is too low to 

significantly contribute to 

nonattainment. * * *.’’ 

Nevertheless, EPA did agree that these 

modeling results were a relevant piece 

of information that could be useful 

when considered in conjunction with 

other information. EPA stated that these 

modeling results do support the 

conclusion that there is not significant 

transport of ozone from Colorado to 

other states with violations of the 

NAAQS: ‘‘ * * * [h]owever, as a 

reflection of emission levels, the 

relatively (to the 1997 8-hour ozone 

NAAQS) moderate concentrations in 

eastern Colorado * * * somewhat 

reduce the probability of significant 

contribution from Colorado emission 

sources to considerably farther 

downwind nonattainment areas such as 

St. Louis, Missouri, and Chicago, 

Illinois.’’ (See 75 FR 16034–35). The 

commenter suggests that EPA approved 

the State’s submission based wholly 

upon technical support that EPA itself 

rejected and this is incorrect. 

Comment No. 4—The commenter 

reiterated its concern that the Colorado 

section 110(a)(2)(D) submission was 

deficient because it did not strictly 

follow the commenter’s summary of the 

structure of the analysis of interstate 

transport in the NOX SIP Call: (a) The 

overall nature of the ozone problem; (b) 

the extent of downwind nonattainment 

problems to which upwind State’s 

emissions are linked; (c) the ambient 

impact of the emissions from upwind 

States’ sources on the downwind 

nonattainment problems; and (d) the 

availability of high cost-effective control 

measures for upwind emissions. 

EPA Response—EPA disagrees with 

the commenter’s view that any analysis 

of interstate transport must follow a 

specific formulaic structure to be 

approvable. As noted above, EPA issued 

specific guidance to states making 

recommendations for section 

110(a)(2)(D) SIP submissions for the 

1997 8-hour ozone NAAQS. Within that 

guidance, EPA recommended various 

types of information that states might 

wish to consider in the process of 

evaluating whether their sources 

contributed significantly to 

nonattainment in other states. EPA has 

concluded that the submission from 

Colorado, augmented by EPA’s own 

analysis, sufficiently establishes that 

Colorado sources do not significantly 

contribute to violations of the 1997 8- 

hour ozone NAAQS in other states. As 

noted above, EPA believes that the 

state’s submission, and EPA’s analysis 

of it, address the same conceptual 

considerations that the commenter 

advocated. 

Comment No. 5—The commenter 

asserted that Colorado and EPA 

provided ‘‘no analysis’’ of the 

contribution from Colorado to 

downwind states and no ‘‘actual 

assessment’’ of the significance of any 

such contribution. 

EPA Response—EPA disagrees with 

the commenter’s position. The 

commenter again assumes that section 

110(a)(2)(D) explicitly requires the type 

of modeling analysis that the 

commenter advocates throughout its 

comments. Because the commenter 

apparently views the NOX SIP Call as 

the applicable guidance, the commenter 

contends that any analytical approach 

that is not identical to that approach is 

impermissible. In addition, the 

commenter overlooks the fact that in 

other actions based upon section 

110(a)(2)(D), EPA has also used a variety 

of analytical approaches, short of 

modeling, to evaluate whether specific 

states are significantly contributing to 

violations of the NAAQS in another 

state (e.g., the west coast states that EPA 

concluded should not be part of the 

geographic region of the CAIR rule 

based upon qualitative factors, and not 

by the zero out modeling EPA deemed 

necessary for some other States). 

In the proposed approval, EPA 

explained that other forms of available 

information were sufficient to make the 

determination that there is no 

significant contribution from Colorado 

sources to downwind nonattainment of 

the 1997 8-hour ozone NAAQS. As 

stated in the proposal: 

‘‘EPA’s evaluation of whether emissions 

from Colorado contribute significantly to 

ozone nonattainment in these areas [St. Louis 

and Chicago] relies on an examination of a 

variety of data and analysis that provide 

insight on ozone transport from Colorado to 

these two areas. Because EPA does not have 

detailed modeling for Colorado and nearby 

downwind states, our approach does not rely 

on a quantitative determination of Colorado’s 

contribution, as EPA did for other states in 

its CAIR rulemaking, but on a weight-ofevidence analysis based on qualitative 

assessments and estimates of the relevant 

factors. While conclusions reached for each 

of the factors considered in the following 

analysis are not in and by themselves 

determinative, consideration of all of these 

factors provides a reliable qualitative 

conclusion on whether Colorado’s emissions 

are likely to contribute significantly to 

nonattainment in the St. Louis and the 

Illinois/Wisconsin areas.’’ 

EPA acknowledged that the various 

forms of information considered in the 

proposal (such as distance, orientation 

of surface and regional transport winds, 

back trajectory analyses, monitoring 

data) were not individually outcome 

determinative, but concluded that when 

taken together served to establish that 

Colorado sources do not significantly 

contribute to downwind nonattainment 

of the 1997 8-hour ozone NAAQS in 

other states. Thus, contrary to the 

commenter’s assertion, EPA did perform 

an ‘‘analysis’’ and an ‘‘assessment’’ that 

was a reasonable basis for its conclusion 

that emissions from Colorado do not 

contribute significantly to downwind 

ozone nonattainment, using a 

combination of quantitative data and 

qualitative analyses. EPA does not agree 

that only the type of analysis advocated 

by the commenter could adequately 

evaluate the issue and support a rational 

determination in this instance. 

Comment No. 6—The commenter 

objected to EPA’s proposed approval 

because Colorado assessed impacts in 

downwind states by considering 

monitoring data in those states as a 

means of evaluating significant 

contribution to nonattainment. In other 


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31310 Federal Register / Vol. 75, No. 106 / Thursday, June 3, 2010 / Rules and Regulations 

7 Michigan v. U.S. EPA, 213 F.3d 663, 674–681 

(D.C. Cir. 2000); North Carolina v. EPA, 531 F.3d 

896, 913–916 (D.C. Cir. 2008) (upholding EPA 

approach to determining threshold despite 

remanding other aspects of CAIR). 

8 2006 Guidance, p. 5. 

9 ‘‘Based on this approach, we predicted that in 

the absence of additional control measures, 47 

counties with air quality monitors [emphasis ours] 

would violate the 8-hour ozone NAAQS in 2010 

* * *.’’ From the CAIR proposed rule of January 30, 

2004 (69 FR 4566, 4581). The NOX SIP call 

proposed rule action reads: ‘‘* * * For current 

nonattainment areas, EPA used air quality data for 

the period 1993 through 1995 to determine which 

counties are violating the 1-hour and/or 8-hour 

NAAQS. These are the most recent 3 years of fully 

quality assured data which were available in time 

for this assessment,’’ 62 FR 60336. 

words, the commenter is concerned that 

Colorado did not assess impacts in areas 

that have no monitor. The commenter 

likewise objected to EPA’s 

‘‘endorsement’’ of this approach. The 

commenter argued that this reliance on 

monitor data is inconsistent with both 

section 110(a)(2)(D) and with EPA’s 

guidance, by which the commenter 

evidently means the NOX SIP Call. In 

support of this assertion, the commenter 

quoted from the NOX SIP Call proposal 

in which EPA addressed the proper 

interpretation of the statutory phrase 

‘‘contribute significantly to 

nonattainment:’’ 

‘‘The EPA proposes to interpret this term to 

refer to air quality and not to be limited to 

currently-designated nonattainment areas. 

Section 110(a)(2)(D) does not refer to 

‘nonattainment areas,’ which is a phrase that 

EPA interprets to refer to areas that are 

designated nonattainment under section 

107(section 107(d)(1)(A)(I))’’ 

According to the commenter, this 

statement, and similar ones in the 

context of the final NOX SIP Call 

rulemaking, establish that states and 

EPA cannot utilize monitoring data to 

evaluate the existence of, and extent of, 

interstate transport. Furthermore, the 

commenter interprets the reference to 

‘‘air quality’’ in these statements to 

support its contention, amplified in 

later comments, that EPA must evaluate 

significant contribution in areas in 

which there is no monitored 

nonattainment. 

EPA Response—EPA disagrees with 

the commenter’s arguments. First, the 

commenter misunderstands the point 

that EPA was making in the quoted 

statement from the NOX SIP Call 

proposal (and that EPA has 

subsequently made in the context of 

CAIR). When EPA stated that it would 

evaluate impacts on air quality in 

downwind states, independent of the 

current formal ‘‘designation’’ of such 

downwind states, it was not referring to 

air quality in the absence of monitor 

data. EPA’s point was that it was 

inappropriate to wait for either initial 

designations of nonattainment for a new 

NAAQS under section 107(d)(1), or for 

a redesignation to nonattainment for an 

existing NAAQS under section 

107(d)(3), before EPA could assess 

whether there is significant contribution 

to nonattainment of a NAAQS in 

another state. 

For example, in the case of initial 

designations, section 107(d) 

contemplates a process and timeline for 

initial designations that could well 

extend for two or three years following 

the promulgation of a new or revised 

NAAQS. By contrast, section 110(a)(1) 

requires states to make SIP submissions 

that address section 110(a)(2)(D) and 

interstate transport ‘‘within 3 years or 

such shorter period as the Administrator 

may prescribe’’ of EPA’s promulgation of 

a new or revised NAAQS. This schedule 

does not support a reading of section 

110(a)(2)(D) that is dependent upon 

formal designations having occurred 

first. This is a key reason why EPA 

determined that it was appropriate to 

evaluate interstate transport based upon 

monitor data, not designation status, in 

the CAIR rulemaking. 

The commenter’s misunderstanding 

of EPA’s statement concerning 

designation status evidently caused the 

commenter to believe that EPA’s 

assessment of interstate transport in the 

NOX SIP Call was not limited to 

evaluation of downwind areas with 

monitors. This is simply incorrect. In 

both the NOX SIP Call and CAIR, EPA 

evaluated significant contribution to 

nonattainment as measured or predicted 

at monitors. For example, in the 

technical analysis for the NOX SIP Call, 

EPA specifically evaluated the impacts 

of emissions from upwind states on 

monitors located in downwind states. 

The NOX SIP Call did not evaluate 

impacts at points without monitors, nor 

did the CAIR rulemaking. EPA believes 

that this approach to evaluating 

significant contribution is correct under 

section 110(a)(2)(D), and EPA’s general 

approach to this threshold 

determination has not been disturbed by 

the courts.7

Finally, EPA disagrees with the 

commenter’s argument that the 

assessment of significant contribution to 

downwind nonattainment must include 

evaluation of impacts on non-monitored 

areas. First, neither section 

110(a)(2)(D)(i)(I) provisions, nor the EPA 

guidance issued for the 1997 8-hour 

ozone NAAQS on August 15, 2006, 

support the commenter’s position, as 

neither refers to any explicit mandatory 

or recommended approach to assess air 

quality in non-monitored areas.8 The 

same focus on monitored data as a 

means of assessing interstate transport is 

found in the NOX SIP Call and in CAIR. 

An initial step in both the NOX SIP Call 

and CAIR was the identification of areas 

with current monitored violations of the 

ozone and/or PM2.5 NAAQS.9 The 

subsequent modeling analyses for 

NAAQS violations in future years (2007 

for the SIP Call and 2010 for CAIR) 

likewise evaluated future violations at 

monitors in areas identified in the 

initial step. Thus, the commenter is 

simply in error that EPA has not 

previously evaluated the presence and 

extent of interstate transport under 

section 110(a)(2)(D) by focusing on 

monitoring data. Indeed, such 

monitoring data was at the core of both 

of these efforts. In neither of these 

rulemakings did EPA evaluate 

significant contribution to 

nonattainment in areas in which there 

was no monitor. This is reasonable and 

appropriate, because data from a 

properly placed Federal reference 

method monitor is the way in which 

EPA ascertains that there is a violation 

of the 1997 8-hour ozone NAAQS in a 

particular area. Put another way, in 

order for there to be significant 

contribution to nonattainment for the 

1997 8-hour ozone NAAQS, there must 

be a monitor with data showing a 

violation of that NAAQS. EPA has 

concluded that by considering data from 

monitored areas, its assessment of 

whether emissions from Colorado 

contribute significantly to ozone 

nonattainment in downwind States is 

consistent with the 2006 Guidance, and 

with the approach used by both the 

CAIR rule and the NOX SIP Call. 

Comment No. 7—In support of its 

comments that EPA should assess 

significant contribution to 

nonattainment in nonmonitored areas, 

the commenter argued that existing 

modeling performed by another 

organization ‘‘indicates that large areas 

of neighboring states will be likely to 

violate the ozone NAAQS.’’ According 

to the commenter, these likely 

‘‘‘violations’’ of the ozone NAAQS were 

predicted for the year 2018, as reflected 

in a slide from a July 30, 2008 

presentation before the Western 

Regional Air Partnership (‘‘Review of 

Ozone Performance in WRAP Modeling 

and Relevant to Future Regional Ozone 

Planning’’). The commenter asserted 

that: ‘‘Slide 28 of this presentation 

displays projected 4th highest 8-hour 

ozone reading for 2018 and indicates 

that air quality in areas such as northern 

New Mexico, western Wyoming, 

southern Utah, and central Arizona will 

exceed and/or violate the 1997 ozone 


emcdonald on DSK2BSOYB1PROD with RULES
Federal Register / Vol. 75, No. 106 / Thursday, June 3, 2010 / Rules and Regulations 31311 

10The presentation is available for review as 

Document ID # EPA–R08–OAR–2007–1032–0007.8 

at Regulations.gov, Docket ID # EPA–R08–OAR– 

2007–1032. 

11Stoeckenius, T.E., C.A. Emery, T.P. Shah, J.R. 

Johnson, L.K. Parker, A.K. Pollack, 2009. ‘‘Air 

Quality Modeling Study for the Four Corners 

Region,’’ pp. ES–3, ES–4, 3–4, 3–12, 3–30, 5–1. 

Prepared for the New Mexico Environment 

Department, Air Quality Bureau, Santa Fe, NM, by 

ENVIRON International Corporation, Novato, CA. 

12The southwestern area referred to by the 

commenter includes portions of Washington, Iron, 

Kane, and Garfield Counties. 

13See UBAQS, pp. 4–27 to 4–29. 

14EPA, Guidance on the Use of Models and other 

Analyses for Demonstrating Attainment of Air 

Quality Goals for Ozone, PM2.5 and Regional Haze. 

Office of Air Quality Planning and Standards, Air 

Modeling Group. Research Triangle Park, North 

Carolina (2007), available at http://www.epa.gov/ 

scram001/guidance/guide/final-03-pm-rhguidance.pdf. 

15 DVC × RRF = DVF. 

NAAQS * * *.’’ 10 In short, the 

commenter argues that modeling 

performed by the WRAP establishes that 

there will be violations of the 1997 8- 

hour ozone NAAQS in 2018 in nonmonitored areas of states adjacent to 

Colorado. 

EPA Response—EPA disagrees with 

this comment on several grounds. First, 

as explained in response to other 

comments, EPA does not agree that it is 

appropriate to evaluate significant 

contribution to nonattainment for the 

1997 8-hour ozone NAAQS by modeling 

ambient levels in areas where there is 

no monitor to provide data to establish 

a violation of the NAAQS in question. 

Section 110(a)(2)(D) does not require 

such an approach, EPA has not taken 

this approach in the NOx SIP Call or 

other rulemakings under section 

110(a)(2)(D), and EPA’s prior analytical 

approach has not been disturbed by the 

courts. 

Second, the commenter’s own 

description of the ozone concentrations 

predicted for the year 2018 as projecting 

‘‘violations’’ of the ozone NAAQS is 

inaccurate. Within the same sentence, 

quoted above, slide 28 is described as 

displaying the projected 4th max ozone 

reading for the year 2018, and as 

indicating that ‘‘* * * air quality * * * 

will exceed or violate [emphasis ours] 

the 1997 ozone NAAQS.’’ By definition, 

a one year value of the 4th max above 

the NAAQS only constitutes an 

exceedance of the NAAQS; to constitute 

a violation of the 1997 8-hour ozone 

NAAQS, the standard must be exceeded 

for three consecutive years at the same 

monitor. Thus, even if the WRAP 

presentation submitted by the 

commenter were technically sound, the 

conclusion drawn from it by the 

commenter is inaccurate and does not 

support its claim of projected violations 

of the NAAQS in large areas (monitored 

or unmonitored) of Colorado’s 

neighboring States. 

Finally, EPA has reviewed the WRAP 

presentation submitted by the 

commenter, and believes that there was 

a substantial error in the WRAP 

modeling software that led to 

overestimation of ground level ozone 

concentrations. A recent study 

conducted by Environ for the Four 

Corners Air Quality Task Force 

(FCAQTF; Stoeckenius et al., 2009) has 

demonstrated that excessive vertical 

transport in the CMAQ and CAMx 

models over high terrain was 

responsible for overestimated ground 

level ozone concentrations due to 

downward transport of stratospheric 

ozone.11 Environ has developed revised 

vertical velocity algorithms in a new 

version of CAMx that eliminated the 

excessive downward transport of ozone 

from the top layers of the model. This 

revised version of the model is now 

being used in a number of applications 

throughout high terrain areas in the 

West. In conclusion, EPA believes that 

this key inadequacy of the WRAP 

model, noted above, makes it 

inappropriate support for the 

commenter’s concerns about large 

expanses of 8-hour ozone nonattainment 

areas projected for 2018 in areas without 

monitors. 

Comment No. 8—As additional 

support for its assertion that EPA should 

require modeling to assess ambient 

levels in unmonitored portions of other 

states, the commenter relied on an 

additional study entitled the ‘‘Uinta 

Basin Air Quality Study (UBAQS).’’ The 

commenter argued that UBAQS further 

supports its concern that Colorado and 

EPA, having limited the evaluation of 

downwind impacts only to areas with 

monitors, failed to assess ozone 

nonattainment in non-monitored areas. 

According to the commenter, UBAQS 

modeling results show that: (a) The 

Wasatch front region is currently 

exceeding and will exceed in 2012 the 

1997 8-hour ozone NAAQS; and (b) 

based on 2005 meteorological data, 

portions of the four counties in the 

southwest corner of Utah are also 

currently in nonattainment and will be 

in nonattainment in 2012.12

EPA Response—As noted above, EPA 

does not agree that it is appropriate to 

assess significant contribution to 

nonattainment for the 1997 8-hour 

ozone NAAQS in the way advocated by 

the commenter. Even taking the UBAQS 

modeling results at face value, however, 

EPA does not agree that the 8-hour 

ozone nonattainment (current and 

projected) in the Wasatch Front Range 

area supports the commenter’s concerns 

about the need to evaluate the 

possibility of significant contribution to 

nonattainment in non-monitored areas. 

EPA sees several problems with the 

commenter’s interpretation of the 

UBAQS analysis results for counties in 

Utah’s southwestern corner: ‘‘based on 

2005 meteorological data, portions of 

Washington, Iron, Kane, and Garfield 

Counties are also in nonattainment and 

will be in nonattainment in 2012.’’ 

First, the commenter’s interpretation 

of the predicted ozone concentrations 

shown in Figures 4–3a and 4–3b (pages 

5 and 6 of the comment letter) is 

inaccurate. A close review of the legend 

in these figures indicates that the 

highest ozone concentrations predicted 

by the model for portions of the 

counties noted above are somewhere 

between 81.00 and 85.99 ppb, but it is 

not specified. If it is actually predicted 

smaller than or equal to 84.9 ppb then 

the area is attaining the 1997 8-hour 

ozone NAAQS, if it is predicted as 

greater than 84.9 ppb then it is not 

attaining those NAAQS. Thus, the 

current and predicted design values for 

the southwestern Utah area identified in 

Figures 4–3a and 4–3b could both be in 

attainment or both in nonattainment, or 

one of them in attainment and the other 

in nonattainment, for the 1997 8-hour 

ozone NAAQS. EPA does not believe 

that this evidence adequately 

establishes that one or both areas 

definitely violate the NAAQS, even if 

the information were taken at face 

value. 

Second, even if the design values 

predicted for these unmonitored areas 

were at the top of the 81.00–85.99 ppb 

range, their reliability would remain 

questionable. The UBAQS itself 

identifies and illustrates major 

shortcomings of its modeling analysis, 

only to neglect assessing the impact of 

these shortcomings on the modeling 

results.13 The study deviates in at least 

two significant ways from EPA’s 2007 

guidance on SIP modeling.14 One issue 

is the UBAQS modeling reliance on 

fewer than the five years of data 

recommended by EPA to generate a 

current 8-hour ozone design value 

(DVC). UBAQS relaxed this requirement 

so that sites with as little as 1 year of 

data were included as DVCs in the 

analysis. The other issue is the 

computation of the relative responsive 

factor (RRF), which directly affects the 

modeling’s future design value (DVF).15

Again due to unavailability of data 

satisfying EPA’s recommendation that 

the RRF be based on a minimum of five 

days of ozone concentrations above 85 


emcdonald on DSK2BSOYB1PROD with RULES
31312 Federal Register / Vol. 75, No. 106 / Thursday, June 3, 2010 / Rules and Regulations 

16See UBAQS, p. 4–28 

17See, for example, ’’Colorado Annual Monitoring 

Network Plan’’ dated 2009–2010. Plan is available 

for review at the regulations.gov Web site under 

Docket ID No. EPA–R08–OAR–2007–1032. 

18WG’s April 9, 2010 comment letter, pp. 9–10. 

Complete versions of the EPA comment letters 

referenced here were attached to the comment as 

Exhibits 3 through 6, and are viewable on the 

Regulations.gov Web site as Documents ID No. 

EPA–R08–OAR–2007–1032–0007.4 through 1032– 

0007.7. 

ppb, UBAQS modeling uses RRFs based 

on one or more days of ozone 

concentrations above 70 ppb.16 EPA 

concludes that the modeling analysis 

results used by the WG are unreliable 

for projecting non-attainment status and 

therefore do not support its comments. 

Comment No. 9—In support of its 

arguments that EPA should not assess 

significant contribution to 

nonattainment through evaluation of 

impacts at monitors instead of modeling 

impacts where there is no such monitor, 

the commenter cited a past statement by 

EPA to the effect that the monitor 

network in the western United States 

needs to be expanded. The quoted 

statements included EPA’s observation 

that ‘‘[v]irtually all States east of the 

Mississippi River have at least two to 

four non-urban O3 monitors, while 

many large mid-western and western 

States have one or no non-urban 

monitors.’’ 74 FR 34525 (July 16, 2009). 

From this statement, the commenter 

argues that it is not appropriate for EPA 

to limit evaluation of significant 

contribution to nonattainment of the 

ozone NAAQS in other states relying on 

monitoring data instead of modeling 

ambient levels. 

EPA Response—EPA does not 

disagree that there are relatively few 

monitors in the western states, and that 

relatively few monitors are currently 

located in non-urban areas of western 

states. However, the commenter failed 

to note that the quoted statement from 

EPA concerning the adequacy of 

western monitors came from the 

Agency’s July 16, 2009, proposed 

rulemaking entitled ‘‘Ambient Ozone 

Monitoring Regulations: Revisions to 

Network Design Requirements.’’ This 

statement was thus taken out of context, 

because EPA was in that proposal 

referring to changes in state monitoring 

networks that it anticipates will be 

necessary in order to implement not the 

1997 8-hour ozone NAAQS that are the 

subject of this rulemaking, but rather the 

next iteration of the ozone NAAQS for 

which there are concerns that there will 

be a need to evaluate ambient levels in 

previously unmonitored areas of the 

western United States. The fact that 

additional monitors may be necessary in 

the future for newer ozone NAAQS does 

not automatically mean that the existing 

ozone monitoring networks are 

insufficient for the 1997 8-hour ozone 

NAAQS, as the commenter implies. 

Indeed, states submit annual monitor 

network reports to EPA and EPA 

evaluates these to insure that they meet 

the applicable requirements. 

For example, Colorado itself submits 

just such a report on an annual basis, 

and EPA reviews it for adequacy.17 All 

other states submit comparable reports. 

Absent a specific concern that another 

state’s current monitor network is 

inadequate to evaluate ambient levels of 

the 1997 8-hour ozone NAAQS, EPA has 

no reason to believe that the evaluation 

of possible significant contribution from 

Colorado sources in reliance on those 

monitors is incorrect. 

Comment No. 10—The commenter 

objected to EPA’s proposed approval of 

the Colorado SIP submission because 

neither Colorado nor EPA performed a 

specific modeling analysis to assure that 

emissions from Colorado sources do not 

significantly contribute to 

nonattainment in downwind States. 

According to the commenter, EPA’s 

decision to use a qualitative approach to 

determine whether emissions from 

Colorado contribute significantly to 

downwind nonattainment is not 

consistent with its own preparation of a 

regional model to evaluate such impacts 

from other states as part of CAIR. 

EPA Response—EPA disagrees with 

the commenter’s belief that only 

modeling can establish whether or not 

there is significant contribution from 

one state to another. First, as noted 

above, EPA does not believe that section 

110(a)(2)(D) requires modeling. While 

modeling can be useful, EPA believes 

that other forms of analysis can be 

sufficient to evaluate whether or not 

there is significant contribution to 

nonattainment. For this reason, EPA’s 

2006 guidance recommended other 

forms of information that states might 

wish to evaluate as part of their section 

110(a)(2)(D) submissions for the 1997 8- 

hour ozone NAAQS. EPA has concluded 

that its qualitative approach to the 

assessment of significant contribution to 

downwind ozone nonattainment is 

consistent with EPA’s 2006 Guidance. 

Second, EPA notes that the 

commenter’s position also reflects a 

misunderstanding of the approach EPA 

used in the remanded CAIR due to an 

exclusive focus on those States that 

were selected for the modeling analysis. 

A wider understanding of the CAIR 

approach would recognize that EPA 

decided, based on other criteria, that it 

was not necessary to conduct modeling 

for certain western states: ‘‘[i]n 

analyzing significant contribution to 

nonattainment, we determined it was 

reasonable to exclude the Western U.S., 

including the States of Washington, 

Idaho, Oregon, California, Nevada, Utah, 

and Arizona from further analysis due 

to geography, meteorology, and 

topography. Based on these factors we 

concluded that the PM2.5 and 8-hour 

ozone nonattainment problems are not 

likely to be affected significantly by 

pollution transported across these 

States’ boundaries * * *.’’ (69 FR 4581, 

January 30, 2004). 

EPA has taken a similar approach to 

assess whether Colorado contributes 

significantly to violations of the 1997 8- 

hour ozone NAAQS in downwind 

states. In the proposed action, EPA 

explained several forms of substantive 

and technically valid evidence that led 

to the conclusion that emissions from 

the Colorado sources do not contribute 

significantly to nonattainment, in 

accordance with the requirement of 

Section 110(a)(2)(D). 

Comment No. 11—In further support 

of its argument that EPA must use 

modeling to evaluate whether there is 

significant contribution to 

nonattainment under section 

110(a)(2)(D), the commenter noted that 

EPA itself asks other agencies to 

perform such modeling in other 

contexts. As examples, the commenter 

cited four examples in which EPA 

commented on actions by other agencies 

in which EPA recommended the use of 

modeling analysis to assess ozone 

impacts prior to authorizing oil and gas 

development projects. As supporting 

material, the comment includes 

quotations from and references to EPA 

letters to Federal Agencies on assessing 

impacts of oil and gas development 

projects.18 The commenter questioned 

why EPA’s recommendation for such an 

approach in its comments to other 

Federal Agencies, did not result in its 

use of the same approach to evaluate the 

impacts from Colorado emissions and to 

insure compliance with Section 

110(a)(2)(D)(i)(I). The commenter 

reasoned that the emissions that would 

result from the actions at issue in the 

other agency decisions, such as selected 

oil and gas drilling projects, would be 

of less magnitude and importance that 

the statewide emissions at issue in an 

evaluation under section 110(a)(2)(D). 

EPA Response—As explained above, 

EPA disagrees with the commenter’s 

fundamental argument that modeling is 

mandatory in all instances in order to 

evaluate significant contribution to 

nonattainment, whether by section 


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Federal Register / Vol. 75, No. 106 / Thursday, June 3, 2010 / Rules and Regulations 31313 

19See 69 FR 4581, January 30, 2004. 

20See, e.g., BCCA v. EPA, 355 F.3d 817 (5th Cir. 

2003). 

21 75 FR 16034, March 31, 2010. 22 ‘‘As discussed above, EPA applied a multifactor approach to identify the amounts of NOX

emissions that contribute significantly to 

nonattainment * * *.’’ 1998 SIP Call, 63 FR 57381, 

October 27, 1998. 

110(a)(2)(D), by EPA guidance, or by 

past EPA precedent. EPA’s applicable 

guidance made recommendations as to 

different approaches that could lead to 

demonstration of the satisfaction of the 

interstate transport requirements for 

significant contribution to 

nonattainment in other states. Even 

EPA’s own CAIR analysis relied on a 

combination of qualitative and 

quantitative analyses, as explained 

above. EPA’s CAIR analysis excluded 

certain western states on the basis of a 

qualitative assessment of topography, 

geography, and meteorology.19

EPA believes that the commenter’s 

references to EPA statements 

commenting on the actions of other 

agencies are inapposite. As the 

commenter is aware, those comments 

were made in the context of the 

evaluation of the impacts of various 

Federal actions pursuant to NEPA, not 

the Clean Air Act. As explained above, 

in the context of section 110(a)(2)(D), 

EPA does not agree that modeling is 

always required to make that different 

evaluation, and EPA itself has relied on 

other more qualitative evidence when it 

deemed that evidence sufficient to reach 

a reasoned determination. 

Comment No. 12—In further support 

of its argument that EPA should always 

require modeling to evaluate significant 

contribution to nonattainment, the 

commenter referred to EPA regulations 

governing nonattainment SIPs. The 

commenter noted 40 CFR 51.112(a)(1), 

which states that: ‘‘[t]he adequacy of a 

control strategy shall be demonstrated 

by means of applicable air quality 

models, data bases, and other 

requirements specified in appendix W 

of [Part 51] (Guideline on Air Quality 

Models).’’ The commenter argues that 

this regulation appears to support the 

commenter’s position that modeling is 

required to satisfy the significant 

contribution element of 110(a)(2)(D). 

Response: EPA disagrees with this 

comment. The cited language implies 

that the need for control strategy 

requirements has already been 

demonstrated, and sets a modeling 

analysis requirement to demonstrate the 

adequacy of the control strategy 

developed to achieve the reductions 

necessary to prevent an area’s air quality 

from continuing to violate the NAAQS. 

EPA’s determination that emissions 

from Colorado do not contribute 

significantly to nonattainment for the 

1997 8-hour ozone standard in any other 

state eliminates the need for a control 

strategy aimed at satisfying the section 

110(a)(2)(D) requirements. Moreover, 

EPA interprets the language at 40 CFR 

51.112(a): ‘‘[e]ach plan must 

demonstrate that the measures, rules, 

and regulations contained in it are 

adequate to provide for the timely 

attainment and maintenance of the 

national standard that it implements,’’ to 

refer to modeling for attainment 

demonstrations, an integral part of 

nonattainment area SIPs under part D of 

the CAA. This interpretation was 

upheld by the Sixth Circuit Court of 

Appeals. Wall v. U.S. EPA, 265 F.3d 

426, 436 (6th Cir. 2001). Thus, the 

commenter’s cited regulation is not 

relevant to EPA’s technical 

demonstration assessing whether 

emissions from Colorado contribute 

significantly to nonattainment in any 

other states under section 110(a)(2)(D). 

Comment No. 13—The commenter 

also objected to EPA’s proposed 

approval of the Colorado submission on 

the grounds that it was based upon a 

‘‘weight-of-evidence analysis,’’ and that 

no such weight of evidence test appears 

in the CAA generally, or in section 

110(a)(2)(D) in particular. According to 

the commenter, there is no regulatory 

support for using a ‘‘weight-of-evidence’’ 

approach to assessing air quality 

impacts. The commenter asserted that 

EPA neither cited nor quoted 

regulations or policy that provides for 

this, and failed to lend any specific 

meaning to the phrase through its 

proposed approval. Finally, the 

commenter asserted, without 

explaining, its belief that EPA failed to 

address ‘‘several relevant factors related 

to the determination of whether 

Colorado contributes significantly to 

nonattainment undermines the agency’s 

reliance on any ‘weight-of-evidence’ 

approach.’’ 

EPA Response—The fact that neither 

the CAA generally, nor section 

110(a)(2)(D) specifically, include the 

explicit phrase ‘‘weight of evidence’’ 

does not mean that it is inappropriate 

for EPA to use such an approach in this 

context. As explained above, section 

110(a)(2)(D) does not explicitly stipulate 

how EPA is to assess whether there is 

a significant contribution to 

nonattainment in other states. The 

proper consideration, therefore, is 

whether EPA has a rational technical 

basis for its decision. Even if the term 

‘‘weight of evidence’’ does not appear in 

section 110(a)(2)(D) or elsewhere in the 

CAA, courts have recognized EPA’s 

reliance on such an analytical approach 

where reasonable.20 As described above, 

EPA’s guidance issued for the 1997 8- 

hour ozone NAAQS, the Agency 

specifically recommended types of 

information that states might wish to 

rely upon to evaluate the presence of, 

and extent of, instate transport for this 

purpose. EPA believes that a weight of 

evidence approach that properly 

considers appropriate evidence is 

sufficient to make a valid determination, 

as in this case. 

Specifically, EPA’s technical analysis 

in the March 31, 2010, proposed rule 

action underscores its reliance on 

implementation policies set in the EPA 

2006 Guidance: ‘‘EPA’s August 15, 2006, 

guidance to states concerning section 

110(a)(2)(D)(i) recommended various 

methods by which states might evaluate 

whether or not its emissions 

significantly contribute to violations of 

the 1997 ozone standards in another 

state. Among other methods, EPA 

recommended consideration of available 

EPA modeling conducted in 

conjunction with CAIR, or in the 

absence of such EPA modeling, 

consideration of other information such 

as the amount of emissions, the 

geographic location of violating areas, 

meteorological data, or various other 

forms of information that would be 

relevant to assessing the likelihood of 

significant contribution to violations of 

the NAAQS in another state [emphasis 

added].’’ 21 On the basis of this 

guidance, Colorado and EPA chose to 

assess the impacts of emissions from 

Colorado sources on the closest 

downwind nonattainment areas (St. 

Louis, Missouri, and Illinois/Wisconsin 

counties along the southwestern shore 

of Lake Michigan) through a weight of 

evidence approach using quantitative 

information such as Colorado’s distance 

from areas with monitors showing 

violating the NAAQS, modeling results 

outlining wind vectors for regional 

transport of ozone on high ozone days, 

back trajectory analyses for the 

downwind nonattainment areas closest 

to Colorado, and results of modeling 

studies for the nonattainment areas 

specifying the range of wind directions 

along which contributing ozone 

transport occurred. EPA’s use of a 

weight of evidence analysis is by no 

means unusual for the assessment of 

ozone impacts through long range 

transport. The same analytical 

framework was used in the 1998 NOX

SIP Call, as indicated under Section 

II.C., entitled ‘‘Weight-of-Evidence 

Determination of Covered States.’’ 22 The 

differences between the specific types of 

evidence used in the NOX SIP Call and 


emcdonald on DSK2BSOYB1PROD with RULES
31314 Federal Register / Vol. 75, No. 106 / Thursday, June 3, 2010 / Rules and Regulations 

23Reproductions of wind roses are available for 

review under Docket ID No. EPA–R08–OAR–2007– 

1032, and online at: http://home.pes.com/ 

windroses/wrgifs/_6200.GIF; http:// 

www.wrh.noaa.gov/twc/aviation/ 

windrose_TUS.php; and http://www.wrcc.dri.edu/ 

htmlfiles/westwinddir.html 

24See 75 FR 16034–35, and ‘‘State of Colorado 

Implementation Plan to Meet the Requirements of 

Clean Air Act Section 110(a)(2)(D)(i)(I)—Interstate 

Transport Regarding the 1997 8-hour Ozone 

Standard,’’ p. 17, December 12, 2009. 

25 75 FR 16035. 

in EPA’s analysis for this action do not 

invalidate the use of the weight-ofevidence approach. 

As for the commenter’s argument that 

EPA ‘‘fails to lend any specific meaning 

to the phrase through its proposed 

approval,’’ the Agency’s technical 

analysis described in the proposal did 

specify the characteristics, including 

limitations, of a weight of evidence 

analysis: ‘‘[f]urthermore * * * EPA 

notes that no single piece of information 

in the following discussion is by itself 

dispositive of the issue. Instead, the 

total weight of all the evidence taken 

together supports the conclusion that 

emissions from Colorado sources are 

unlikely to contribute significantly to 

violations of the 1997 8-hour ozone 

standard in any other state.’’ (75 FR 

16034). 

Finally, as to the commenter’s 

assertion that EPA failed to consider 

‘‘several relevant factors’’ and thus failed 

to conduct an appropriate weight of 

evidence evaluation, EPA cannot weigh 

the validity of this comment in the 

absence of an explanation of what these 

factors might be. 

Comment No. 14—The commenter 

also objected to EPA’s proposed 

approval of the Colorado submission on 

the grounds that EPA did not assess the 

potential impacts of Colorado sources of 

emissions on violations of the 1997 8- 

hour ozone NAAQS in Arizona 

(Phoenix area), and Utah (Davis County 

area.) 

EPA Response—EPA did not discuss 

or assess potential impacts of Colorado 

emissions on Arizona or Utah in the 

proposal. EPA first notes that, west of 

the Continental Divide the prevailing 

winds generally move from southwesterly or westerly directions, as 

indicated by the typical movement of 

weather systems. 

Also, EPA notes that Davis County 

had a monitor indicating a violation of 

the NAAQS in 2007, but has not since 

then. Thus, there are currently no 

monitors in Utah with data showing 

violations of the 1997 8-hour ozone 

NAAQS and, as a consequence, there 

are no monitors for which it would be 

appropriate to evaluate the possibility of 

significant contribution to 

nonattainment from Colorado sources 

for the 1997 8-hour ozone NAAQS. In 

Arizona, the Maricopa 8-hour ozone 

nonattainment area, which includes 

Phoenix, does have monitors indicating 

a violation of this NAAQS. However, 

Phoenix lies approximately 600 miles 

southwest of the Colorado DMA/NFR 

area, and this area is generally upwind 

from Colorado sources. Emissions from 

Colorado would have to be affected by 

strong winds from the northeast, which 

are very infrequent, in order to 

contribute significantly to 8-hour ozone 

nonattainment in the Phoenix area. The 

rarity of northeasterly winds in Arizona 

may be gauged by images of wind roses 

for Phoenix and Tucson.23

Comment No. 15—The commenter 

argued that both Colorado and EPA 

relied inappropriately on a flawed 

ozone ‘‘nonattainment’’ SIP for the 

DMA/NFR nonattainment area as a basis 

for the proposed approval. According to 

the commenter, EPA cannot approve 

Colorado’s section 110(a)(2)(d) 

submission because it relies heavily on 

the requirements of the ozone 

nonattainment area SIP for the DMA/ 

NFR nonattainment area. The 

commenter argued that ‘‘many’’ of the 

provisions of the nonattainment area 

SIP are themselves flawed or deficient. 

As examples, the commenter outlined 

alleged deficiencies in the Colorado Air 

Quality Control Commission’s 

Regulation No. 7, RACT requirements 

for NOX emissions, exemptions for 

certain source categories of NOX

emissions, and other unspecified 

provisions in the DMA/NFR 

nonattainment area SIP. 

EPA Response—EPA disagrees with 

the commenter’s position that its 

proposed approval relied heavily on the 

nonattainment area SIP for the DMA/ 

NFR area, and that as a consequence 

EPA cannot approve the Colorado 

section 110(a)(2)(D) submission for the 

significant contribution element for the 

1997 8-hour ozone NAAQS. First, EPA 

notes that its reliance on material from, 

and related to, the ‘‘8-Hour Ozone 

Attainment Plan’’ was limited to 

considering the modeling results 

indicating a quick drop in ambient 

ozone levels from the DMA/NFR area to 

the easternmost Colorado counties. EPA 

did not purport to pass upon the 

adequacy or approvability of each and 

every aspect of that nonattainment area 

SIP by referring to the modeling results 

as a source of relevant facts to be taken 

into consideration. 

Second, the proposal made clear that 

EPA’s interpretation of the significance 

of this information is different from 

Colorado’s: ‘‘EPA does not accept the 

State of Colorado Interstate Transport 

SIP assessment that these results 

demonstrate that ‘the magnitude of 

ozone transport from Colorado to other 

states is too low to significantly 

contribute to nonattainment in * * * 

any other state with respect to the 0.08 

ppb NAAQS.’ ’’ 24 EPA explained its 

own view that the relatively moderate 

ozone concentrations in eastern 

Colorado (compared to the 1997 8-hour 

ozone NAAQS), while not excluding a 

potential significant contribution from 

Colorado emissions to downwind 

nonattainment areas, reduce the 

probability of its occurrence.25 This is 

neither the key piece, nor even one of 

the key pieces, of evidence upon which 

EPA relies for its determination that 

emissions from Colorado sources do not 

contribute significantly to downwind 

nonattainment areas. To the contrary, 

EPA considered a variety of technical 

data and analyses of transport factors 

wholly independent of and 

substantively stronger than the 

modeling results connected with the 

DMA/NFR nonattainment area SIP. 

In addition, EPA notes that the 

commenter did not specify exactly how 

each of the purported flaws in the 

Colorado nonattainment area SIP for the 

DMA/NFR area could affect the 

reliability of the modeling results EPA 

used in the proposed rule, or the 

weight-of-evidence analysis that was the 

basis of the proposed approval of the 

Colorado section 110(a)(2)(D) 

submission for the significant 

contribution element. For example, the 

commenter did not explain what impact 

the specific alleged defects in 

Regulation 7 would have on emissions, 

and how any increases in emissions as 

a result of those defects would in turn 

result in significant contribution to 

nonattainment in other states. Absent 

more data or explanation supporting the 

commenter’s general concerns, EPA 

cannot conclude that these alleged 

nonattainment SIP ‘‘defects,’’ even if 

EPA ultimately agrees that they are 

statutory or regulatory deficiencies, 

result in additional emissions that have 

such impacts. Given this uncertainty as 

to the impacts of the alleged defects, if 

any, EPA does not agree that it is per se 

inappropriate to consider the modeling 

results in the very limited way that the 

Agency has done so in this action. 

Furthermore, EPA does not agree with 

the commenter that, given the alleged 

defects, EPA cannot approve the 

Colorado interstate transport SIP for the 

significant contribution element of 

section 110(a)(2)(D)(i)(I) until the 

alleged defects are resolved. As 

discussed below, the first step of the 

process to determine whether this 


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Federal Register / Vol. 75, No. 106 / Thursday, June 3, 2010 / Rules and Regulations 31315 

element is satisfied is the factual 

determination of whether a State’s 

emissions contribute significantly to 

nonattainment in downwind areas. If 

this factual finding is in the negative, as 

is the case for EPA’s assessment of the 

contribution from emissions from 

Colorado, then section 110(a)(2)(D)(i)(I) 

does not require any changes to a state’s 

provisions. 

Finally, EPA does not agree that it is 

appropriate to address the commenter’s 

specific substantive comments about the 

merits of Rule 7 in the context of this 

action on the section 110(a)(2)(D) SIP 

submission. Colorado has separately 

submitted its ozone nonattainment SIP 

for the DMA/NFR nonattainment area to 

the Agency, and that submission will 

ultimately be the subject of another 

rulemaking in which EPA will evaluate 

and act upon that specific SIP 

submission. The commenter may 

resubmit its specific substantive 

comments on Rule 7, and any other 

comments on the nonattainment SIP for 

the DMA/NFR area, in that later 

rulemaking. 

Comment No. 16—The commenter 

also objected to EPA’s proposed 

approval because ‘‘Colorado’s SIP, as 

written, simply does not contain any 

language that prohibits emissions that 

contribute significantly to 

nonattainment in any other state.’’ The 

commenter also notes that EPA did not 

assess whether the SIP does or does not 

contain such provisions. The 

commenter appears to have argued that 

110(a)(2)(D)(i) requires a state SIP to 

contain an explicit provision literally 

prohibiting emissions that contribute 

significantly to nonattainment in any 

other state and that, in order to approve 

the Colorado interstate transport SIP, 

EPA must examine the SIP to determine 

whether it contains such an explicit 

prohibition. 

EPA Response—EPA disagrees with 

the commenter’s interpretation of the 

statutory requirements. Section 

110(a)(2)(D)(i) has no language that 

requires a SIP to contain a specific 

provision literally prohibiting 

significant contribution to 

nonattainment in any other state, or, for 

that matter, to contain any particular 

words or generic prohibitions. Instead, 

EPA believes that the statute requires a 

state’s SIP to contain substantive 

emission limits or other provisions that 

in fact ensure that sources located 

within the state will not produce 

emissions that have such an effect in 

other states. Therefore, EPA believes 

that satisfaction of the ‘‘significant 

contribution’’ requirement is not to be 

demonstrated through a literal 

requirement for a prohibition of the type 

advocated by the commenter. 

EPA’s past application of section 

110(a)(2)(D) did not require the literal 

prohibition advocated by the 

commenter. For example, in 1998 NOX

SIP call (63 FR 57356, October 27, 1998) 

EPA indicated that ‘‘the term ‘prohibit’ 

means that SIPs must eliminate those 

amounts of emissions determined to 

contribute significantly to 

nonattainment * * *.’’ As a result, the 

first step of the process to determine 

whether this statutory requirement is 

satisfied is the factual determination of 

whether a State’s emissions contribute 

significantly to nonattainment in 

downwind areas. See 2005 CAIR Rule 

(70 FR 25162) and 1998 NOX SIP Call 

(63 FR 57356). If this factual finding is 

in the negative, as is the case for EPA’s 

assessment of the contribution from 

emissions from Colorado, then section 

110(a)(2)(D)(i)(I) does not require any 

changes to a state’s SIP. If, however, the 

evaluation reveals that there is such a 

significant contribution to 

nonattainment in other states, then EPA 

requires the state to adopt substantive 

provisions to eliminate those emissions. 

The state could achieve these reductions 

through traditional command and 

control programs, or at its own election, 

through participation in a cap and trade 

program. Thus, EPA’s approach in this 

action is consistent with the Agency’s 

interpretation of 110(a)(2)(D)(i) in the 

2006 guidance, the CAIR Rule, and the 

NOX SIP call, none of which required 

the pro forma literal ‘‘prohibition’’ of the 

type advocated by the commenter. 

Comment No. 17—The commenter 

noted a provision for stationary source 

permitting in the Colorado SIP that the 

commenter argued is inadequate to 

ensure that sources in Colorado will not 

significantly contribute to 

nonattainment in other states. The 

commenter also argued that Colorado 

does not sufficiently implement a 

requirement in the SIP to ensure 

stationary sources do not cause a 

violation of the 1997 8-hour ozone 

NAAQS, because Colorado guidelines 

do not uniformly require ozone 

modeling for such sources. The 

commenter stated that EPA cannot 

approve the Colorado interstate 

transport SIP unless the issues 

commenter identifies are first resolved. 

EPA Response—As discussed above, 

the first step of the process to determine 

whether the ‘‘significant contribution’’ 

requirement is satisfied is the factual 

determination of whether a State’s 

emissions contribute significantly to 

nonattainment in downwind areas. If 

the factual finding is in the negative, as 

is the case for EPA’s assessment of the 

contribution from emissions from 

Colorado, then section 110(a)(2)(D)(i)(I) 

does not require any substantive 

changes to a state’s SIP, nor does it 

require EPA to determine whether a 

state should require modeling in all 

permitting actions. As discussed above, 

EPA’s approach in this action is 

consistent with the Agency’s 

interpretation of 110(a)(2)(D)(i) in the 

2006 guidance, the CAIR Rule and the 

NOX SIP Call. Therefore, EPA disagrees 

with the comment that EPA cannot 

approve the Colorado interstate 

transport SIP unless EPA addresses 

specific provisions and state guidelines 

for permitting stationary sources. 

Comment No. 18—The commenter 

argued that EPA cannot approve the 

section 110(a)(2)(D) submission from 

Colorado because the state and EPA did 

not comply with 110(l). Evidently, the 

commenter believes that the section 

110(a)(2)(D) submission is a revision to 

the SIP that will interfere with 

attainment of the 2006 PM2.5 NAAQS 

and the 2008 ozone NAAQS. The 

commenter argued that a section 110(l) 

analysis must consider all NAAQS once 

they are promulgated, and argued that 

EPA took the same position in 

proposing to disapprove a PM10

maintenance plan. 

EPA Response—EPA agrees that a 

required section 110(l) analysis must 

consider the potential impact of a 

proposed SIP revision on attainment 

and maintenance of all NAAQS that are 

in effect and impacted by a given SIP 

revision. However, EPA disagrees that it 

failed to comply with the requirements 

of section 110(l) or that section 110(l) 

requires disapproval of the SIP 

submission at issue here. 

Section 110(l) provides in part that: 

‘‘[t]he Administrator shall not approve a 

revision of a plan if the revision would 

interfere with any applicable 

requirement concerning attainment and 

reasonable further progress * * *, or 

any other applicable requirement of this 

chapter.’’ EPA has consistently 

interpreted Section 110(l) as not 

requiring a new attainment 

demonstration for every SIP submission. 

EPA has further concluded that 

preservation of the status quo air quality 

during the time new attainment 

demonstrations are being prepared will 

prevent interference with the states’ 

obligations to develop timely attainment 

demonstrations. 70 FR 58134, 58199 

(October 5, 2005); 70 FR 17029, 17033 

(April 4, 2005); 70 FR 53, 57 (January 3, 

2005); 70 FR 28429, 28431 (May 18, 

2005). 

Colorado’s submission is the initial 

submission by the state to address the 

significant contribution to 


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31316 Federal Register / Vol. 75, No. 106 / Thursday, June 3, 2010 / Rules and Regulations 

nonattainment element of 110(a)(2)(D)(i) 

for the 1997 8-hour ozone. This 

submission does not revise or remove 

any existing emissions limit for any 

NAAQS, or any other existing 

substantive SIP provisions relevant to 

the 1997 8-hour ozone NAAQS. Simply 

put, it does not make any substantive 

revision that could result in any change 

in emissions. As a result, the 

submission does not relax any existing 

requirements or alter the status quo air 

quality. Therefore, approval of the 

submission will not interfere with 

attainment or maintenance of any 

NAAQS. 

EPA’s discussion in the notice cited 

by the commenter is consistent with this 

interpretation. In the cited action, EPA 

noted that ‘‘Utah ha[d] either removed or 

altered a number of stationary source 

requirements,’’ creating the possibility of 

a relaxation of SIP requirements 

interfering with attainment, a possibility 

that is not present here. See 74 FR 

62727 (December 1, 2009). Thus, the 

action cited by the commenter is clearly 

distinguishable. 

The commenter did not provide any 

specific basis for concluding that 

approval of this SIP submission would 

interfere with attainment or 

maintenance of a NAAQS, or with any 

other applicable requirement of the 

Clean Air Act. EPA concludes that 

approval of the submission will not 

make the status quo air quality worse, 

and is in fact consistent with the 

development of an overall plan capable 

of meeting the Act’s attainment 

requirements. Accordingly, even 

assuming that section 110(l) applies to 

this submission, EPA finds that 

approval of the submission is consistent 

with the requirements of section 110(l). 

III. Section 110(l) 

Section 110(l) of the Clean Air Act 

states that a SIP revision cannot be 

approved if the revision would interfere 

with any applicable requirement 

concerning attainment and reasonable 

further progress towards attainment of 

the NAAQS or any other applicable 

requirements of the Act. In this action, 

EPA is approving portions of the 

Colorado interstate transport SIP 

addressing the ‘‘significant contribution’’ 

requirements of section 110(a)(2)(D)(i)(I) 

for the 1997 8-hour ozone NAAQS. As 

discussed above in EPA’s response to 

comments, the SIP revision that EPA is 

partially approving in this action does 

not revise or remove any existing 

emissions limit for any NAAQS, or any 

other existing substantive SIP 

provisions relevant to the 1997 8-hour 

ozone NAAQS. As a result, the SIP 

revision does not relax any existing 

requirements or alter the status quo air 

quality. Furthermore, EPA has 

determined that the revision is 

consistent with all applicable Federal 

requirements and will not interfere with 

requirements of the Act related to 

administrative or procedural provisions. 

Therefore, the revision does not 

interfere with attainment or 

maintenance of the NAAQS or other 

applicable requirements of the Act. 

IV. Final Action 

EPA is partially approving the 

Interstate Transport SIP submitted by 

the State of Colorado on June 18, 2009. 

Specifically, in this action EPA is 

approving the portions of that SIP 

submission that address the requirement 

of Section 110(a)(2)(D)(i)(I) that 

emissions from sources in that state do 

not ‘‘significantly contribute’’ to 

violations of the 1997 8-hour ozone 

NAAQS in any other state. EPA has 

concluded that the state’s submission, 

and additional evidence evaluated by 

EPA, establish that emissions from 

Colorado sources do not have such an 

impact on other states for purposes of 

the 1997 8-hour ozone NAAQS. 

Therefore, the state’s SIP does not need 

to include additional substantive 

controls to reduce emissions for 

purposes of section 110(a)(2)(D)(i)(I) for 

these NAAQS. At a later date, EPA will 

act on those portions of the Interstate 

Transport SIP that address the 

requirement of section 110(a)(2)(D)(i)(I) 

that emissions from the state’s sources 

do not ‘‘interfere with maintenance’’ of 

the 1997 8-hour ozone NAAQS in any 

other state. 

V. Statutory and Executive Order 

Review 

Under the Clean Air Act, the 

Administrator is required to approve a 

SIP submission that complies with the 

provisions of the Act and applicable 

Federal regulations. 42 U.S.C. 7410(k); 

40 CFR 52.02(a). Thus, in reviewing SIP 

submissions, EPA’s role is to approve 

state choices, provided that they meet 

the criteria of the Clean Air Act. 

Accordingly, this action merely 

approves state law as meeting Federal 

requirements and does not impose 

additional requirements beyond those 

imposed by state law. For that reason, 

this action: 

• Is not a ‘‘significant regulatory 

action’’ subject to review by the Office 

of Management and Budget under 

Executive Order 12866 (58 FR 51735, 

October 4, 1993); 

• Does not impose an information 

collection burden under the provisions 

of the Paperwork Reduction Act (44 

U.S.C. 3501 et seq.); 

• Is certified as not having a 

significant economic impact on a 

substantial number of small entities 

under the Regulatory Flexibility Act (5 

U.S.C. 601 et seq.); 

• Does not contain any unfunded 

mandate or significantly or uniquely 

affect small governments, as described 

in the Unfunded Mandates Reform Act 

of 1995 (Pub. L. 104–4); 

• Does not have Federalism 

implications as specified in Executive 

Order 13132 (64 FR 43255, August 10, 

1999); 

• Is not an economically significant 

regulatory action based on health or 

safety risks subject to Executive Order 

13045 (62 FR 19885, April 23, 1997); 

• Is not a significant regulatory action 

subject to Executive Order 13211 (66 FR 

28355, May 22, 2001); 

• is not subject to requirements of 

Section 12(d) of the National 

Technology Transfer and Advancement 

Act of 1995 (15 U.S.C. 272 note) because 

application of those requirements would 

be inconsistent with the Clean Air Act; 

and 

• Does not provide EPA with the 

discretionary authority to address, as 

appropriate, disproportionate human 

health or environmental effects, using 

practicable and legally permissible 

methods, under Executive Order 12898 

(59 FR 7629, February 16, 1994). 

In addition, this rule does not have 

tribal implications as specified by 

Executive Order 13175 (65 FR 67249, 

November 9, 2000), because the SIP is 

not approved to apply in Indian country 

located in the state, and EPA notes that 

it will not impose substantial direct 

costs on tribal governments or preempt 

tribal law. 

The Congressional Review Act, 5 

U.S.C. 801 et seq., as added by the Small 

Business Regulatory Enforcement 

Fairness Act of 1996, generally provides 

that before a rule may take effect, the 

agency promulgating the rule must 

submit a rule report, which includes a 

copy of the rule, to each House of the 

Congress and to the Comptroller General 

of the United States. EPA will submit a 

report containing this action and other 

required information to the U.S. Senate, 

the U.S. House of Representatives, and 

the Comptroller General of the United 

States prior to publication of the rule in 

the Federal Register. A major rule 

cannot take effect until 60 days after it 

is published in the Federal Register. 

This action is not a ‘‘major rule’’ as 

defined by 5 U.S.C. 804(2). 

Under section 307(b)(1) of the Clean 

Air Act, petitions for judicial review of 

this action must be filed in the United 

States Court of Appeals for the 

appropriate circuit by August 2, 2010. 


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Federal Register / Vol. 75, No. 106 / Thursday, June 3, 2010 / Rules and Regulations 31317 

Filing a petition for reconsideration by 

the Administrator of this final rule does 

not affect the finality of this action for 

the purposes of judicial review nor does 

it extend the time within which a 

petition for judicial review may be filed, 

and shall not postpone the effectiveness 

of such rule or action. This action may 

not be challenged later in proceedings to 

enforce its requirements. (See section 

307(b)(2).) 

List of Subjects in 40 CFR Part 52 

Environmental protection, Air 

pollution control, Carbon moNOXide, 

Incorporation by reference, 

Intergovernmental relations, Lead, 

Nitrogen dioxide, Ozone, Particulate 

matter, Reporting and recordkeeping 

requirements, Sulfur oxides, Volatile 

organic compounds. 

Authority: 42 U.S.C. 7401 et seq. 

Dated: May 17, 2010. 

Carol Rushin, 

Deputy Regional Administrator, Region 8. 

40 CFR part 52 is amended as follows: 

PART 52—[AMENDED] 

■ 1. The authority citation for Part 52 

continues to read as follows: 

Authority: 42 U.S.C. 7401 et seq. 

Subpart G—Colorado 

■ 2. Section 52.352 is added to subpart 

G to read as follows: 

§ 52.352 Interstate transport. 

Addition to the Colorado State 

Implementation Plan of the Colorado 

Interstate Transport SIP regarding the 

1997 8–Hour Ozone Standard for the 

‘‘significant contribution’’ requirement, 

as adopted by the Colorado Air Quality 

Control Commission on December 30, 

2008, State effective January 30, 2009, 

and submitted by the Governor’s 

designee on June 18, 2009. 

[FR Doc. 2010–13050 Filed 6–2–10; 8:45 am] 

BILLING CODE 6560–50–P 

ENVIRONMENTAL PROTECTION 

AGENCY 

40 CFR Part 63 

[EPA–HQ–OAR–2008–0053; FRL–9158–1] 

RIN 2060–AN47 

National Emission Standards for 

Hazardous Air Pollutants: Area Source 

Standards for Paints and Allied 

Products Manufacturing; Amendments 

AGENCY: Environmental Protection 

Agency (EPA). 

ACTION: Direct final rule. 

SUMMARY: EPA is taking direct final 

action on amendments to the paints and 

allied products manufacturing area 

source rule. With this direct final rule, 

EPA is amending the definition of 

‘‘material containing hazardous air 

pollutants.’’ It was not EPA’s intent to 

omit the part of this definition that 

addresses non-carcinogens, and this 

omission could potentially and 

erroneously include facilities as 

applicable to the rule when they should 

not be covered. 

This action clarifies text of the 

National Emission Standards for 

Hazardous Air Pollutants: Paints and 

Allied Products Manufacturing Area 

Source Standards which was published 

on December 3, 2009. This action will 

not change the level of health protection 

the final rule provides or the standards 

and other requirements established by 

the rule. 

DATES: This direct final rule is effective 

on September 16, 2010 without further 

notice, unless EPA receives relevant 

adverse comment by July 19, 2010. If 

EPA receives relevant adverse comment, 

we will publish a timely withdrawal in 

the Federal Register informing the 

public that the amendments in this rule 

will not take effect. 

ADDRESSES: Submit your comments, 

identified by Docket ID No. EPA–HQ– 

OAR–2008–0053, by one of the 

following methods: 

• Federal eRulemaking Portal: 

www.regulations.gov: Follow the 

instructions for submitting comments. 

• Agency Web site: www.epa.gov/oar/ 

docket.html. Follow the instructions for 

submitting comments on the EPA Air 

and Radiation Docket Web site. 

• E-mail: a-and-r-Docket@epa.gov. 

Include Docket ID No. EPA–HQ–OAR– 

2008–0053 in the subject line of the 

message. 

• Fax: Send comments to (202) 566– 

9744, Attention Docket ID No. EPA– 

HQ–OAR–2008–0053. 

• Mail: Area Source NESHAP for 

Paints and Allied Products 

Manufacturing Docket, Environmental 

Protection Agency, Air and Radiation 

Docket and Information Center, 

Mailcode: 2822T, 1200 Pennsylvania 

Avenue, 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 17th Street, 

NW., Washington, DC 20503. 

• Hand Delivery: EPA Docket Center, 

Public Reading Room, EPA West, 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. 

Instructions: Direct your comments to 

Docket ID No. EPA–HQ–OAR–2008– 

0053. EPA’s policy is that all comments 

received 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 e-mail. 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 e-mail comment directly 

to EPA without going through http:// 

www.regulations.gov, your e-mail 

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. 

Docket: EPA has established a docket 

for this action under Docket ID No. 

EPA–HQ–OAR–2008–0053. All 

documents in the docket are listed in 

the Federal Docket Management System 

index at http://www.regulations.gov. 

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 form. 

Publicly available docket materials are 

available either electronically through 

http://www.regulations.gov or in hard 

copy at the EPA Docket Center, Public 

Reading Room, 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 


emcdonald on DSK2BSOYB1PROD with RULES