## Responses to Significant Comments on the

2012 Proposed Rule on the

Revision to Ambient Nitrogen

Dioxide Monitoring Requirements

( October 19, 2012 ; 7 7 FR 64244 )

Docket Number EPA

- HQ

- OAR

- 20 12

- 0486

U.S. Environmental Protection Agency

## Table of Contents

I. Introduction

II. Responses to comments on the revision of the near

- road NO 2 monitor implementation

schedule.

III. Responses to comments on the change in the NO 2 Annual Monitoring Network Plan

approval authority.

IV. Responses to comments on general monitoring and implementation.

## Frequently Cited Documents

The following documents are frequently cited throughout the EPA’s response to comments, often

by means of the short names listed below:

Preamble to the final rule:

Preamble to the Final Rule on Revision to Ambient Nitrogen Dioxide Monitoring Requirements;

to be published in the Federal Register in January or February of 2012.

Proposal notice:

Revision to Ambient Nitrogen Dioxide Monitoring Requiremen ts: Proposed Rule.

77 FR 34244, October 19, 2012.

## Acronyms and Abbreviations

EPA U.S. Environmental Protection Agency

NAA QS National Ambient Air Quality Standard

NO 2 

## Nitrogen Dioxide

CAA Clean Air Act

## I. Introduction

This document, together with the preamble to the final rule on the Revision to Ambient

Nitrogen Dioxide Monitoring Requirements, presents the responses of the Environmental

Protection Agency (EPA) to the public comments received on the 2012 Revisions to Ambient

Nitrogen Dioxide Monitoring Requirements proposal notice (77 FR 64244). All significant

issues raised in timely public comments have been addressed.

In cases where there were a number of comments that addressed similar issues, this

response

- to

- comments document does not generally cross

- reference each response to the

commenter(s) who raised the particular issue involved, although commenters are identified in

some cases where they provided particularly detailed comments that were used to frame the

overall response on an issue.

The responses presented in this document are intended to augment the responses to

comments that appear in the preamble to the final rule or to address comments not discussed in

the preamble to the final rule. Although portions of the preamble to the final rule are paraphrased

in this document where useful to add clarity to responses, to the extent any ambiguity is

i ntroduced by this paraphrasing, the preamble itself remains the definitive statement of the

rationale for the revisions to the standards adopted in the final rule.

In many instances, particular responses presented in this document include cross

references to responses on related issues that are located either in the preamble to the final rule,

or in this Response to Comments document. In other instances

, the comment is appropriately

addressed by the a gency’s discussion in other parts of the record. All issues on which the

Administrator is taking final action in the final rule are addressed in the rulemaking record.

Accordingly, this Response to Comments document, together with the preamble to the

final rule and the Notice of Proposed Rulemaking should be considered collectively as the EPA’s

response to all of the significant comments submitted on the EPA ’s 2012 Revisions to Ambient

Nitrogen Dioxide Monitoring Requirements propos ed rule. This document incorporates directly

or by reference the significant public comments addressed in the preamble to the final rule

, as

well as other significant public comment s that were submitted on the proposed rule.

Consistent with the final decisions presented in the notice of final r ulemaking, comments

on the following topics are addressed in this document: c hanges to the a mbient Nitrogen

Dioxide ( NO 2 ) m onitoring r equirem ents (section II .A ) ; c hanges in Annual Monitoring Network

Plan a pproval a uthority (section II.B ) ; and responses to general monitoring and implementation

issues.

## II. Responses to C omments on the R evision of the N ear

- road NO 2



## M onitor I mplementation S chedule

While a majority of commenters who made statements regarding the proposed revision to

adjust the dates by which near

- road NO 2 monitors are required were supportive, the EPA

received one comment against the proposed revisions.

Comment: One commenter stated that the proposed revision would lead to a trend in which

the EPA will “...continuously revise the deadline, as there wi ll always be funding

issues in our current economy.” The commenter goes on to suggest that

postponing may also be interpreted to mean that the EPA is minimizing the

priority for near

- road NO 2 monitoring.

Response: As noted in the preamble to the final rule (Section II.A.2)

, the EPA is not

minimizing ambient air monitoring in the near

- road environment through this

action. The EPA is taking action to adjust the timeline by which required near

road monitors must be in place to reflect th e reality of limited resources between

the federal, state, and local air agencies. The EPA is not reducing the amount of

required monitoring, but is adjusting the schedule to match the forecasted

available funding, which will have to occur over multiple years.



## III. Responses to C omments on the C hange in the NO 2 

## Annual

Monitoring Network Plan A pproval A uthority

All public comments received on the proposal to shift the approval authority of state

Annual Monitoring Network Plans from the EPA Administrator to the EPA Regional

Administrators were fully supportive. As discussed in the preamble to the final rule (Section

II.B)

, the proposal is being finalized as proposed.



## IV. Response to Comments on General Monitoring and

Implementation Issues

Comment: Multiple state and multi

- state representative groups commented that full funding

for capital and long

- term operations and maintenance need to be provided in order

for states to implement the near

- road NO 2 network. For example, the South

Carolina Department of Health and Environmental Control stated that “...[Clean

Air Act section 103 funds are] necessary to support implementation and equitable

allocation of [Clean Air Act section] 105 funding be provided for the continued

cost of operations and maintenance of any federally mandated ambient monitoring

networks.”Response: As discussed in the preamble to the final rule, t he EPA recognizes that there are

funding and resource shortfalls at the federal, state

, and local levels. Although the

requirement to install these required near

- road NO 2 monitors is not dependent on

federal funds being available, the EPA will continue to attempt to secure

sufficient funding for the implementation of the near

- road NO 2 networ k. The

EPA believes it will be able to identify those grant funds over time, allowing the

network to phase

- in as was proposed and finalized

. The EPA will continue to

work w ith States to identify strategies for optimizing networks as a mechanism

for controlling ongoing maintenance and operational costs. Both the annual

monitoring network planning process and 5

- year network assessments provide

pathways for states to engage in such conversations with their respective Regional

Offices.

Comment: One commenter stated that this rule suggests “...to increase placement of air

quality monitors near ‘major roads in larger urban areas’.”

Response: The EPA notes that this rulemaking is not increasing the placement (or number)

of NO 2 monitors near

- roads in larger urban areas. The action of requiring near

road NO 2 monitors was promulgated in the 2010 NO 2 NAAQS rulemaking (75

FR 6474). This rulemaking is only changing the dates when required near

- road

NO 2 monitors are to be implemented

.

Comment: One commenter stated that the EPA should avoid near

- road NO 2 monitoring,

which highlights “...only the worst areas for emissions instead of focusing on the

more complete, and accurate picture of our nation’s success in improving air

q uality.” The commenter also states that required monitoring should instead

balance air quality monitor placement between “high and low travelled areas” as a

means to obtain an assessment of an entire county’s air quality.

Response: We note that the rationale behind the requirements to monitoring NO 2 near

roads, as articulated in the 2010 NO 2 NAAQS rulemaking (75 FR 6474), is to

support the NAAQS which was revised to protect against exposures to peak NO 2 concentrations that can occur anywhere in an area, which includes the near

- road

environment.

Comment: One commenter stated “the phased approach allows for time to analyze the results

from the first phase implemented in January of [2014] in order to determine

whether future proposed phases are required. The EPA should analyze data and

experience gained from the first phase and work with state and local agencies to

determine whether the future phase, especially the third phase due in January

2017, is necessary.”Response: The re quirements for near

- road NO 2 monitoring, promulgated in the 2010 NO 2 NAAQS revision, were based on available data, or lack thereof, in supporting the

NAAQS. The EPA anticipates that any revision to the number or focus of NO 2

monitors would be part of the next NO 2 NAAQS review, where new monitoring

data would be considered along with available health data and analysis used to

evaluate the suitability of the NAAQS itself.

Comment: Multiple commenters requested that the EPA address nonattainment issues that

may arise from forthcoming near

- road data. Sever al of those same commenters

went on to request that the EPA work with states to determine how the near

- road

data will be used in determining potential n onattainment areas as well as

implications to air permitting programs. Another commenter questioned how the

staggered implementation of required near

- road NO 2 monitors will affect the

designation process, particularly if phasing

- in the monitors would result in

multiple rounds of designations. This commenter noted that each round of

designations requires intensive staff time and resources, and suggested that the

EPA consider a single round of designations resulting from near

- road NO 2 data,

when all the monitors have reported a suf ficient amount of data.

Response: Once three years of air quality data have been collected from a given newly sited

monitor, the EPA will be able to assess this data and work with the state s to

determine appropriate steps to address designations and permi tting

- related issues

. On January 20, 2012, t he EPA completed initial designations for the 2010 NO2

NAAQS for all areas of the country. Once 3 years of air quality data are available

from a monitor , the EPA has discretion under the CAA to redesignate areas as

appropriate from ‘‘unclassifiable’’ to ‘‘attainment’’ or ‘‘nonattainment.’’ For

monitors deployed beginning in 2014, sufficient data to evaluate potential

redesignations would be available after 201 6 (77 FR 9534

- 9535)

. The EPA is

aware that phasing

- in the new monitors will mean that 3 years of data will not be

available for all monitors at the same time. The EPA is also aware of the federal

and state resources required to conduct designations, and we anticipate taking this

type of information into account in working with states to determine appropriate

next steps.