From: "Frey, Nathan J." <Nathan_J._Frey@omb.eop.gov>

To: Lydia Wegman/RTP/USEPA/US@EPA Date: 06/12/2012 04:15 PM Subject: Summary of Interagency Comments Under EO 12866/13563: National Ambient Air Quality

Standards for Particulate Matter NPRM

Attached please find a summary of interagency comments under EO 12866/13563 regarding issues related to monitoring and implementatio n on the EPA proposed rule regarding National Ambient Air Quality Standards for Particulate Matter:
RIN 2060

- AO47.

Thank you and please let me know if you have any questions.

### Summary of Interagency Working Comments on Draft Language under

EO12866/13563 Interagency Review. Subject to Further Policy Review.

Monitoring and Implementation

• Some commenters would like to understand whether proposed changes to the monitoring program (or any other changes that would not affect initial attainment designation) are mandated by the relevant court orders. If not specifically required, commenters recommend that changes to monitoring programs be removed from this proposed rule and be proposed separately, giving additional time to understand the implications of monitoring changes, the interplay between near

- ro ad monitoring for different pollutants, and how near

road monitoring will affect future modeling and NAAQS standards.

• The draft NPRM appears to link the near

- road monitor with the conformity process, which would be a substantial change in existing procedu res and could make conformity determinations more difficult. The references to consideration of the near

- road data for comparison to present versus future PM2.5 NAAQS are still not clear. I t appears that EPA’s intent would be that the data would not be

c onsidered for the NAAQS being proposed here, but for future NAAQS. If so, then that concept is not clear from the language in the preamble. Understanding that the data would be ready for use as soon as 2018, it sounds like the near

road data could be use d for comparison to new PM2.5 24 hour NAAQS presently being proposed, at least. Also, to introduce a change in the conformity process as part of a NAAQS rulemaking is not appropriate.

• The NPRM removes the existing flexibility to determine whether speci fic receptors are appropriate for comparing to the NAAQS under transportation conformity, but preserves this flexibility for permitting agencies making decisions with respect to stationary sources. Transportation projects should be given the same flexibil ities as stationary sources.

• The proposed lowering of the standard will almost certainly increase the number of nonattainment areas that will need to comply with the transportation conformity process, creating an additional burden on transportation agenc ies and project sponsors.

• The commenters looking at this question had a concern about the statement that there was “long

- standing” support for these changes. If the changes do come from authority from the 1997 NAAQS, then that foundation should be stat ed more clearly.

• On page 14 of 34 of the attached edited language, the discussion of the use of the

near

- road data for receptor sites on hot spot analyses has been removed, and more general language about how data is “valuable” for transportation conformi ty determinations has been added. Reference to the language used in

### Summary of Interagency Working Comments on Draft Language under

EO12866/13563 Interagency Review. Subject to Further Policy Review.

answer to comment 22, as attached here, would be helpful in describing how the

near

- road data could be “valuable” for determining receptor sites, without creating the specter of requiring monitoring for hot spot analysis from the Friday version of the language.

• Currently, a standardized measurement methodology for PM emissions from aircraft engines does not exist. Since 2010, both EPA and FAA have been working with subject matter experts within the SAE

- International E

- 31 Committee to define, test, and document a standardized measurement methodology for non

- volatile PM emissions. This technical group is approximately 18 months away from establishing a global Aerospace Recommended Practice (ARP), which would be the technical basis for establishing a regulation governing PM emissions from aircraft. In the absence of a standardized method for measuring PM emissions from aircraft engines, commenters find that it would be especially challengin g to evaluate aviation actions for the proposed secondary standard, which is proposed to be based on visibility. There are no adequate tools for measuring or estimating PM emissions from aircraft; thus, it will not be possible to demonstrate compliance the new standards, such as in completing conformity analysis and determinations where needed. The current tools for surrogate emissions estimates are only available for commercial jet aircraft emissions, not for emissions from other aircraft types.

One commenter o bject ed to the original language on page 359/360 that suggests a relationship between the proposed near road PM monitoring network and Transportation Conformity PM hot spot modeling guidance and it must be deleted.
The sentence states “Near road PM 2.5 sites would...by physically requiring monitoring in locations that historically were generally modeled but not monitored.” The revised sentence provided by EPA “ Near

- road PM 2.5 sites would also make measurement data available for complex locations not routinely monitored currently that may be valuable for the implementation of the Agency’s permitting program and transportation conformity determinations” is equally unacceptable. Both sentences suggests a change in EPA’s current Transportation
Conformit y/CAA compliance requirements for transportation projects, insinuating a relationship between modeling and monitoring project impacts which is unsupported. Any such change will have a tremendous impact on transportation projects that are required to meet transportation conformity requirements and is inappropriate to introduce a change in this process in a NAAQS rulemaking.

Applicability of Microscale Monitors for Comparison to Annual PM NAAQS

. Some commenters disagree with EPA’s proposal to add language “that explicitly

### Summary of Interagency Working Comments on Draft Language under

EO12866/13563 Interagency Review. Subject to Further Policy Review.

states that measuring PM 2.5 in micro

- and middle

- scale environments near emissions of mobile sources, such as a highway, does not constitute being impacted by a “unique” source”(p. 356). It is not reasonable to assume that no highways

wo uld represent a unique source. PM emissions resulting from a roadway are very unique to the individual characteristics of that roadway, such as fleet mix, age distribution, level

- of

- service, and road geometry. Commenters do not agree with
EPA’s rational t hat “Mobile sources are rather ubiquitous and, as such, there are many locations throughout an urban area where elevated exposures could occur.” As highlighted in EPA’s 2006 PM 2.5 and PM 10 Hot

- spot Rulemaking for Transportation Conformity, PM emissions are particularly sensitive to diesel emissions (71 FR 12491

- 12492):

a. EPA modeling shows emission factors for heavy

- duty vehicles in the near term are approximately 40

- 50 times higher than gasoline vehicles on a per vehicle basis and 15

- 20 times higher in 2015;
b. Studies show high level of particles in areas with high diesel activity, particularly areas with elevated acceleration or a large number of trucks operating for long periods in close proximity such as around truck routes, freight terminals or truck stops;

c. Study results from a major freeway in Los Angeles “demonstrate that gasoline vehicles do not appear to reliability create higher PM 2.5 concentrations that could create or worsen air quality violations in a
localized area.”

Not all highways, even those with similar levels of AADT, have the same vehicle activity patter ns and characteristics, notably the amount of diesel vehicles. Commenters therefore request maintaining the current capacity for unique sites to be able to be determined on a case

- by

- case basis without adding the explicit provision that all highways are as sumed to not be unique. Section 4.7.1(c)(1) and (2) of Appendix D to 40 CFR Part 58 already provides information on the relationship between microscale sites and representativeness.

Applicability of Near Road Monitor to the NAAQS . Commenters do not belie ve, particularly in the case of PM, that one near road monitor can represent area

- wide exposures. Concentrations of PM in the near road environment are dependent on the nature of traffic on that roadway which can vary considerably. It is additionally

ina ppropriate, particularly in the case of CO and PM, to collocate monitors to measure maximum concentrations of both pollutants. CO is a mobile pollutant driven primarily by gasoline vehicles and PM is driven primarily by diesel vehicles.
EPA has sited rese arch in Transportation Conformity Rule Amendments showing clustering of CO with gasoline vehicles and NOx, PM 2.5 , and PM 2.5

- 10 with diesel

### Summary of Interagency Working Comments on Draft Language under

EO12866/13563 Interagency Review. Subject to Further Policy Review.

vehicles (e.g., heavy

- duty diesel trucks), the positive relationship of PM 2.5 mass and elemental carbon mass (primari ly from diesel exhaust), and concentrations of PM 2.5 significantly associated with diesel vehicles on nearby roadways but not with gasoline vehicles (71 FR 12492).

Commenters request that EPA (a) clarify how any individual roadway is ubiquitous to other roadways in the nonattainment area for PM 2.5 before allowing monitoring results from a single near road monitor near one specific roadway to be used to represent near road or “area

- wide” conditions in a nonattainment area; and (b) provide information to cl arify the scalability of PM 2.5 monitoring results associated with one roadway to other roadways in the CBSA including the magnitude of sensitivity for a variety of variables such as AADT, fleet mix, fleet age distribution, road geometry, level

- of

- service, temporal distribution of VMT, site

- specific meteorological conditions, and others.

Applicability of Receptors for Comparison to Annual PM NAAQS . Any changes in the implementation for PSD permitting and transportation conformity should be

consistent as re lated to the proposed change in the applicability of receptors for comparison to the annual standard. EPA notes in its response to interagency comments that: “...if the proposed PM NAAQS revisions and monitoring regulation clarifications described previously are finalized, permitting agencies will continue to have the flexibility to qualify or disqualify specific receptor locations used in PSD air quality analyses consistent with those provisions.” However, for transportation conformity as discussed in Sectio n G, the change “would mean that micro

- and middle scale sites would be compared to the annual PM 2.5 standard unless the Regional Administrator decides that the site is unique.” EPA proposes to remove the flexibility in the current Transportation Conformity PM hot

- spot guidance for the interagency consultation process to determine whether receptors are appropriate for comparison to the NAAQS, per Section G of the NPRM. Commenters strongly object to this seemingly inconsistent approach and the remov al of flexibility to transportation projects while the same flexibility will continue to be allowed for other permitting agencies. Inconsistencies in the application of the change in annual NAAQS receptor applicability should be resolved and transportatio n project sponsors should continue to have the flexibility to be able to qualify or disqualify specific receptor locations via the interagency consultation process.

Introduction of Secondary Standard . (a) Boundaries. As noted by EPA,
nonattainment boundar ies for areas violating the secondary standard are expected to overlap with the primary standard (p. 384). Commenters support this approach.
Where the area

- specific analysis supports overlapping boundaries, this overlap

### Summary of Interagency Working Comments on Draft Language under

EO12866/13563 Interagency Review. Subject to Further Policy Review.

would promote the most streamlined c ase for areas to address transportation conformity requirements for the secondary standard. (b) EPA also notes that “the same type of emissions sources contribute to concentrations affecting attainment status for both the proposed primary and secondary NAA QS (p. 384). Therefore, commenters suggest that implementation of the standards allow for areas that are nonattainment for both to control for the secondary standard by meeting the transportation conformity requirements for the primary standard.

Impleme ntation of New NAAQS . In context of implementing the proposed revised primary annual PM2.5 NAAQS in nonattainment areas, EPA discusses potentially updating certain polices in the existing implementation rule (p. 394). Commenters strongly encourage EPA to discuss the Agency’s plans on revoking the existing PM2.5 annual standards (15 μg/m3) or solicit comments on this matter. This revocation issue is especially important in the implementation of the conformity provisions of the CAA. The revocation issue w as not applicable (and therefore was not included) in the implementation rule of the 1997 PM2.5 NAAQS.

Additional Burden for Transportation due to New NAAQS . Some commenters express concern regarding a substantial additional burden for transportation

pra ctitioners due to the lowering of the standard from 15 μg/m 3 . (a) Areas newly designated for the lower standard will need to comply with the Transportation Conformity requirements, including integrating these requirements in to their transportation plannin g processes. For areas new to meeting transportation requirements, this may involve building expertise, additional resources to meet requirements, and additional interagency relationship building; (b)To meet project

level requirements, project sponsors mu st complete a hot

- spot analysis for certain projects involving a large amount of diesel traffic. Current guidance on conducting this analysis does not allow a consideration of future background concentrations. Therefore, with the majority of areas expected to be well over the new standard in the near term, project sponsors will at a minimum need to conduct additional no

build analyses and/or will have to mitigate project emissions according to current background despite the project being built in the future ; and (c) additional uncertainty will be introduced should EPA finalize its proposed secondary standard, for which the transportation conformity has yet to be implemented, and if the Agency finalizes changes to the monitoring requirements for the PM 2.5 ann ual standard related to microscale monitoring. It is unclear with a distinct secondary standard how nonattainment boundaries will align for the primary and secondary NAAQS as well as how mobile source emissions budgets will be executed

### Summary of Interagency Working Comments on Draft Language under

EO12866/13563 Interagency Review. Subject to Further Policy Review.