NOTE—NTAA recommends that you begin your Tribe’s comment letter with introductory remarks
regarding the signatory’s position with the Tribe and include somewhere in the letter a description
of the Tribe’s physical environment and any particular concerns the Tribe has with respect to this
proposed rule. The more individualized the letter, the greater its potential impact. Feel free to add
you own arguments, objections, or support for various aspects of the proposal. Comments are due
October 27, 2015.
U.S. Environmental Protection Agency
Mail Code 28221T
Attention Docket ID No. EPA-HQ-OAR-2015-0310
1200 Pennsylvania Ave., NW
Washington, DC, 20460
Subject:
Proposed Revision to the Guideline on Air Quality Models: Enhancements to the
AERMOD Dispersion Modeling System and Incorporation of Approaches to Address Ozone and
Fine Particulate Matter
Introduction
The [NAME OF TRIBE] is pleased to submit these comments and recommendations regarding the U.S.
Environmental Protection Agency’s (EPA)’s proposed Revision to the Guideline on Air Quality Models:
Enhancements to the AERMOD Dispersion Modeling System and Incorporation of Approaches to
Address Ozone and Fine Particulate, 80 Fed. Reg. 45340 (July 29, 2015) (Proposed Guideline).
The [NAME OF TRIBE] approves generally of the Proposed Guideline. However, as a complement to
the [NAME OF TRIBE]’s general approval of the Proposed Guideline, the [NAME OF TRIBE] provides
its comments and recommendation regarding the removal of CALPUFF as a preferred model, the
Prevention of Significant Deterioration increment consumption, modeling for air quality related values,
recommended models and approaches for ozone, and Tribal consultation.
Removing CALPUFF as a Preferred Model
Since 2003, CALPUFF has been EPA’s preferred model for long-range transport (e.g., distances greater
than 50 kilometers (km)) of criteria pollutants from area, point, line, and volume sources.1 However, the
Proposed Guideline provides that CALPUFF shall be removed as a preferred model from EPA’s list of
preferred models. Any future use of CALPUFF for addressing regulatory requirements would subject the
model to alternative model demonstration requirements under Section 3.2.2 of the Proposed Guideline.2
The [NAME OF TRIBE] understands that newer alternative models, such as the Comprehensive Air
Quality Model with Extensions (CAMx) and the Community Multiscale Air Quality (CMAQ) model,
provide a more robust scientific treatment of the important physical processes of pollutant transport,
dispersion, and chemical transformation than CALPUFF; and shall likely have an increasing role in
assessing long-range transport and dispersion of pollutants under the Proposed Guideline. Further,
eliminating CALPUFF as a preferred model should make it easier to obtain approval for using CAMx and
CMAQ based on Section 3.2.2 of the Proposed Guideline. However, CAMx and CMAQ, as well as other
newer, robust models, have very intensive resource requirements for which there is a very limited pool of
qualified individuals who can manage application of the models daily in a permit setting. Most Indian
1
2
Id. at 45349.
Id. at 45360.
Tribes that use CALPUFF currently would not be able to handle such resource requirements nor employ
the necessary individuals to manage daily application of the models.
The [NAME OF TRIBE] recommends that the Proposed Guideline acknowledge the need to use
CALPUFF in the near future based on its historical acceptance by EPA as a preferred model for address
long-range transport of criteria pollutants and air quality related values analyses in regulatory permitting;
and that CALPUFF shall likely continue in such a role in the absence of an alternative preferred model.
Specifically, EPA could provide an “automatic pre-approval” of CALPUFF under Section 3.2.2 of the
Proposed Guideline for situations where application of the model is consistent with its historical use as a
preferred model approved under earlier versions of the Proposed Guideline. This would acknowledge the
continued role of CALPUFF in meeting the expected future regulatory needs for long-range transport
modeling along with reducing the burden on applicants and regulatory agencies where a case-by-case
demonstration is necessitated to show that CALPUFF meets Section 3.2.2 requirements of the Proposed
Guideline.
Prevention of Significant Deterioration Increment Consumption
The [NAME OF TRIBE] has concerns that, because CALPUFF has been removed as a preferred model
for long-range transport of criteria pollutants absent a replacement, some might interpret Prevention of
Significant Deterioration (PSD) increment modeling is no longer necessary for distances greater than 50
km from a source. However, historical experience has demonstrated that Class I PSD increments may be
threatened by the cumulative impacts of multiple distant emission sources. As such, dispersion modeling
and the PSD increment consumption analysis for Class I areas located greater than 50 km from emission
sources shall be absolutely necessary in order to allow Federal Land Managers (FLMs), and Indian Tribes
with redesignated Class I areas, to protect and manage air quality within Class I areas under their
authority.
The preamble of the Proposed Guideline provides that CALPUFF may be used as a screening tool
to support long-range transport PSD increment assessments.3 However, Section 4.2.1 of the Proposed
Guideline does not reference CALPUFF as an applicable screening tool for long-range transport
modeling.4 Further, EPA suggests that the need for such a tool is expected to be limited.5 The [NAME
OF TRIBE] finds that the likelihood of new and modified sources needing to address long-range transport
for Class I PSD increment compliance has been significantly underestimated by EPA, given that air
quality management of Class I areas, by necessity, requires that dispersion modeling extend beyond a
distance of 50 km. As such, the [NAME OF TRIBE] recommends that the Proposed Guideline include a
discussion under Section 4.2.1 about using CALPUFF as an appropriate long-range transport screening
tool.
Modeling for Air Quality Related Values
The Proposed Guideline acknowledges the use of air dispersion models, referenced under
Appendix W of 40 C.F.R. Part 51, in fulfilling the requirements of non-EPA air quality programs.6 The
Proposed Guideline gives particular attention to the authority of FLMs to protect areas listed as Class I
under the PSD program including the air quality related values (AQRVs) associated with such areas. Not
once does the Proposed Guideline make reference to any of the Indian Tribes that have redesignated
portions of their reservations to Class I status, and at least one such Tribe, the Forest County Potawatomi
3
Id. at 45349.
Id. at 45361.
5
Id.
6
Id. at 45366-67.
4
Community, has also adopted AQRVs within its Class I area. The [NAME OF TRIBE] expects that
additional Tribes may also elect to adopt AQRVs in the future. Tribal air agencies, much like FLMs,
have an affirmative responsibility to protect air quality and AQRVs, where applicable, within lands under
their jurisdiction, including those land areas that have been redesignated to Class I status.
Any authority granted to FLMs under Appendix W of 40 C.F.R. Part 51 for protecting air quality
within Class I areas, including AQRVs, is also applicable to Indian Tribes and Tribal air quality
programs. As such, the [NAME OF TRIBE] recommends that Section 6.0 of the Guideline be amended
to acknowledge that Tribal Class I areas also exist and that Tribal air quality agencies have adopted
programs to protect air quality in Class I areas under their jurisdiction including AQRVs in such areas.
Recommended Models and Approaches for Ozone
The [NAME OF TRIBE] appreciates the discussion under Section 5.0 of the Guideline about air quality
modeling for ozone.7 The Forest County Potawatomi Community, as an Indian Tribe with a Tribal Class
I area, lists specifically as an AQRV impacts to vegetation from ozone exposure. Properly managing
ozone as an AQRV within the Tribe’s Class I area shall require a suitable tool for assessing possible
single-source air quality impacts to ozone.
Section 5.3.2 of the Proposed Guideline provides a conceptual approach for determining ozone
from individual emission sources.8 EPA recommends a two-tiered approach9 for which it commits to
develop additional technical tools to assist in single-source ozone modeling efforts.10 The [NAME OF
TRIBE] recommends that EPA expedite the development of these tools for use by regulatory agencies,
including Tribal agencies, given the immediate need for such tools to assess and manage single-source
impacts to listed AQRVs such as ozone.
Tribal Omissions from Proposed Guideline
The [NAME OF TRIBE] recognizes that the Proposed Guideline includes mention of Indian Tribes and
Tribal agencies. However, the [NAME OF TRIBE] finds that there are a number of other places in the
Proposed Guideline where EPA must add reference to Tribes and Tribal agencies to recognize the role
that they have in managing air quality within their reservation boundaries. The [NAME OF TRIBE]
provides, as one example, changes that it recommends to Section 6.0 of the Proposed Guideline
(proposed changes are italicized and underlined).
1. Section 6.1 – Paragraph a), First Sentence: “Other federal agencies and Indian Tribes
have also developed specific modeling approaches…”11
2. Section 6.1- Paragraph b): “…the model user should consult the appropriate federal or
state or Tribal agency…” and “…Other federal and Tribal agencies have developed
specific modeling approaches for their own regulatory or other requirements.”12
7
Id. at 45364.
Id. at 45365.
9
Id.
10
Id. at 45348 (U.S. EPA, 2015. ‘‘Proposed Approach for Demonstrating Ozone PSD Compliance’’, Memorandum to
Docket No. EPA–HQ–OAR–2015–0310 by Tyler J Fox, U.S. EPA/OAQPS, Research Triangle Park, NC. June 30, 2015).
8
11
12
Id. at 45366.
Id.
3. Section 6.2 – After Paragraph a), Insert the following: “Where Tribes have redesignated
lands to Class I status, the applicable Tribal agency has equivalent responsibilities to the
FLMs.”13
4. Section 6.2 – Paragraph b): The FLM and Tribal agency responsibilities include…”, and
“AQRVs are resources identified by the FLM and Tribal agencies...”, and “The FLM and
Tribal agencies take into account…”14
5. Section 6.2 – Paragraph c): “…determination of appropriate analytical methods and
metrics are determined by the FLM and Tribal agencies…”15
6. Section 6.2 – After Paragraph d), Insert the following: “Tribal agencies have also
developed guidance similar to that of the FLMs and users should consult these
documents when addressing Class I impacts on redesignated Tribal lands.”16
7. Section 6.2.1 – After Paragraph b), Insert the following: “In some cases, Tribal agencies
also manage Class I areas for visibility as an AQRV.”17
8. Section 6.2.1.1 – Paragraph a): “The model selection, procedures, and analyses should be
determined in consultation with the appropriate reviewing authority and the affected
FLM(s) and/or Tribal agencies.”18
9. Section 6.2.2 – Paragraph a): “To address the relationships between deposition and
ecosystem effects, the FLM and Tribal agencies have developed estimates of critical
loads.”19
10. Section 6.2.2 – Paragraph b): “The FLM and Tribal deposition modeling
recommendations…” and “Users should consult the latest version of the FLAG report
and relevant FLM and/or Tribal representatives for guidance on the use of models for
deposition. Where the source and receptors are in close proximity, users should contact
the appropriate FLM and/or Tribal agency for application specific guidance.”20
Tribal Consultation
EPA provides that the Proposed Guideline does “not have tribal implications, as specified in
Executive Order 13175.”21 The rationale for EPA’s finding is that the Proposed Guideline “imposes no
requirements on tribal governments.” The [NAME OF TRIBE] finds that EPA does not understand fully
the intent behind EO 13175 as it is not limited to federal actions imposing requirements on tribal
governments. Specifically, section 1(a) of EO 13175 defines “policies that have tribal implications” as:
13
Id.
Id.
15
Id.
16
Id.
17
Id. at 45367.
18
Id.
19
Id.
20
Id.
21
Id. at 45355.
14
[R]egulations, legislative comments or proposed legislation, and other policy statements or actions that
have substantial direct effects on one or more Indian tribes, on the relationship between the Federal
Government and Indian tribes, or on the distribution of power and responsibilities between the Federal
Government and Indian tribes.22
The definition makes no reference to the imposition of requirements on tribal governments although such
requirements are one of many implications that a federal agency action could have on Indian Tribes.
The [NAME OF TRIBE] finds that Proposed Guideline has implications to Indian Tribes beyond
those identified by EPA. Some of these have already been identified by the [NAME OF TRIBE] as they
relate to Tribes that have redesignated or are considering redesignating portions or whole parts of their
reservations as Class I areas. EO 13175 requires EPA to develop an accountability process to ensure
“meaningful and timely input by development of regulatory policies that have tribal implications.” EPA
must develop and implement such a process to fulfill the intent of EO 13175.
Conclusion
In summary, the [NAME OF TRIBE] is pleased to provide the aforementioned comments and
recommendations concerning the Proposed Guideline.
On Behalf of the [NAME OF TRIBE],
NOTE—if appropriate, provide a staff contact whom EPA may contact if it has questions.
22
Executive Order 13175, Consultation and Coordination with Indian Tribal Governments (November 9, 2000) at
http://www.epa.gov/fedrgstr/eo/eo13175.htm (last visited on October 3, 2015).