Regulatory Citation

40 CFR 51.309 (up to date as of 10/15/2024)
Requirements related to the Grand Canyon Visibility Transport Commission.

40 CFR 51.309 (Oct. 15, 2024)

This content is from the eCFR and is authoritative but unofficial.

Title 40 —Protection of Environment
Chapter I —Environmental Protection Agency
Subchapter C —Air Programs
Part 51 —Requirements for Preparation, Adoption, and Submittal of Implementation Plans
Subpart P —Protection of Visibility
Authority: Secs. 110, 114, 121, 160-169, 169A, and 301 of the Clean Air Act, (42 U.S.C. 7410, 7414, 7421, 7470-7479, and 7601).
Source: 45 FR 80089, Dec. 2, 1980, unless otherwise noted.
Authority: 23 U.S.C. 101; 42 U.S.C. 7401-7671q.
Source: 36 FR 22398, Nov. 25, 1971, unless otherwise noted.

§ 51.309 Requirements related to the Grand Canyon Visibility Transport Commission.
(a) What is the purpose of this section? This section establishes the requirements for the first regional haze
implementation plan to address regional haze visibility impairment in the 16 Class I areas covered by the
Grand Canyon Visibility Transport Commission Report. For the period through 2018, certain States
(defined in paragraph (b) of this section as Transport Region States) may choose to implement the
Commission's recommendations within the framework of the national regional haze program and
applicable requirements of the Act by complying with the provisions of this section. If a Transport Region
State submits an implementation plan which is approved by EPA as meeting the requirements of this
section, it will be deemed to comply with the requirements for reasonable progress with respect to the 16
Class I areas for the period from approval of the plan through 2018. Any Transport Region State electing
not to submit an implementation plan under this section is subject to the requirements of § 51.308 in the
same manner and to the same extent as any State not included within the Transport Region. Except as
provided in paragraph (g) of this section, each Transport Region State is also subject to the requirements
of § 51.308 with respect to any other Federal mandatory Class I areas within the State or affected by
emissions from the State.
(b) Definitions. For the purposes of this section:
(1) 16 Class I areas means the following mandatory Class I Federal areas on the Colorado Plateau:
Grand Canyon National Park, Sycamore Canyon Wilderness, Petrified Forest National Park, Mount
Baldy Wilderness, San Pedro Parks Wilderness, Mesa Verde National Park, Weminuche Wilderness,
Black Canyon of the Gunnison Wilderness, West Elk Wilderness, Maroon Bells Wilderness, Flat Tops
Wilderness, Arches National Park, Canyonlands National Park, Capital Reef National Park, Bryce
Canyon National Park, and Zion National Park.
(2) Transport Region State means one of the States that is included within the Transport Region
addressed by the Grand Canyon Visibility Transport Commission (Arizona, California, Colorado,
Idaho, Nevada, New Mexico, Oregon, Utah, and Wyoming).
(3) Commission Report means the report of the Grand Canyon Visibility Transport Commission entitled
“Recommendations for Improving Western Vistas,” dated June 10, 1996.
(4) Fire means wildfire, wildland fire, prescribed fire, and agricultural burning conducted and occurring on
Federal, State, and private wildlands and farmlands.
(5) Milestone means the maximum level of annual regional SO2 emissions, in tons per year, for a given
year, assessed annually, through the year 2018, consistent with paragraph (d)(4) of this section.
40 CFR 51.309(b)(5) (enhanced display)

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40 CFR 51.309 (up to date as of 10/15/2024)
Requirements related to the Grand Canyon Visibility Transport Commission.

40 CFR 51.309(b)(6)

(6) Continuous decline in total mobile source emissions means that the projected level of emissions
from mobile sources of each listed pollutant in 2008, 2013, and 2018, are less than the projected
level of emissions from mobile sources of each listed pollutant for the previous period (i.e., 2008
less than 2003; 2013 less than 2008; and 2018 less than 2013).
(7) Base year means the year for which data for a source included within the program were used by the
WRAP to calculate emissions as a starting point for development of the milestone required by
paragraph (d)(4)(i) of this section.
(8)-(12) [Reserved]
(13) Eligible renewable energy resource, for purposes of 40 CFR 51.309, means electricity generated by
non-nuclear and non-fossil low or no air emission technologies.
(c) Implementation Plan Schedule. Each Transport Region State electing to submit an implementation plan
under this section must submit such a plan no later than December 17, 2007. Indian Tribes may submit
implementation plans after this deadline.
(d) Requirements of the first implementation plan for States electing to adopt all of the recommendations of
the Commission Report. Except as provided for in paragraph (e) of this section, each Transport Region
State must submit an implementation plan that meets the following requirements:
(1) Time period covered. The implementation plan must be effective through December 31, 2018 and
continue in effect until an implementation plan revision is approved by EPA in accordance with §
51.308(f).
(2) Projection of visibility improvement. For each of the 16 mandatory Class I areas located within the
Transport Region State, the plan must include a projection of the improvement in visibility conditions
(expressed in deciviews, and in any additional ambient visibility metrics deemed appropriate by the
State) expected through the year 2018 for the most impaired and least impaired days, based on the
implementation of all measures as required in the Commission report and the provisions in this
section. The projection must be made in consultation with other Transport Region States with
sources which may be reasonably anticipated to contribute to visibility impairment in the relevant
Class I area. The projection may be based on a satisfactory regional analysis.
(3) Treatment of clean-air corridors. The plan must describe and provide for implementation of
comprehensive emission tracking strategies for clean-air corridors to ensure that the visibility does
not degrade on the least-impaired days at any of the 16 Class I areas. The strategy must include:
(i)

An identification of clean-air corridors. The EPA will evaluate the State's identification of such
corridors based upon the reports of the Commission's Meteorology Subcommittee and any
future updates by a successor organization;

(ii) Within areas that are clean-air corridors, an identification of patterns of growth or specific sites
of growth that could cause, or are causing, significant emissions increases that could have, or
are having, visibility impairment at one or more of the 16 Class I areas.
(iii) In areas outside of clean-air corridors, an identification of significant emissions growth that
could begin, or is beginning, to impair the quality of air in the corridor and thereby lead to
visibility degradation for the least-impaired days in one or more of the 16 Class I areas.

40 CFR 51.309(d)(3)(iii) (enhanced display)

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40 CFR 51.309 (up to date as of 10/15/2024)
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40 CFR 51.309(d)(3)(iv)

(iv) If impairment of air quality in clean air corridors is identified pursuant to paragraphs (d)(3)(ii)
and (iii) of this section, an analysis of the effects of increased emissions, including provisions
for the identification of the need for additional emission reductions measures, and
implementation of the additional measures where necessary.
(v) A determination of whether other clean air corridors exist for any of the 16 Class I areas. For
any such clean air corridors, an identification of the necessary measures to protect against
future degradation of air quality in any of the 16 Class I areas.
(4) Implementation of stationary source reductions. The first implementation plan submission must
include:
(i)

Provisions for stationary source emissions of SO2. The plan submission must include a SO2
program that contains quantitative emissions milestones for stationary source SO2 emissions
for each year through 2018. After the first two years of the program, compliance with the annual
milestones may be measured by comparing a three-year rolling average of actual emissions
with a rolling average of the emissions milestones for the same three years. During the first two
years of the program, compliance with the milestones may be measured by a methodology of
the States' choosing, so long as all States in the program use the same methodology.
Compliance with the 2018 milestone shall be measured by comparing actual emissions from
the year 2018 with the 2018 milestone. The milestones must provide for steady and continuing
emissions reductions through 2018 consistent with the Commission's definition of reasonable
progress, its goal of 50 to 70 percent reduction in SO2 emissions from 1990 actual emission
levels by 2040, applicable requirements under the CAA, and the timing of implementation plan
assessments of progress and identification of any deficiencies which will be due in the years
2013 and 2018. The milestones must be shown to provide for greater reasonable progress than
would be achieved by application of BART pursuant to § 51.308(e)(2).

(ii) Documentation of emissions calculation methods for SO2. The plan submission must include
documentation of the specific methodology used to calculate SO2 emissions during the base
year for each emitting unit included in the program. The implementation plan must also provide
for documentation of any change to the specific methodology used to calculate emissions at
any emitting unit for any year after the base year.
(iii) Monitoring, recordkeeping, and reporting of SO2 emissions. The plan submission must include
provisions requiring the monitoring, recordkeeping, and annual reporting of actual stationary
source SO2 emissions within the State. The monitoring, recordkeeping, and reporting data must
be sufficient to determine annually whether the milestone for each year through 2018 is
achieved. The plan submission must provide for reporting of these data by the State to the
Administrator and to the regional planning organization. The plan must provide for retention of
records for at least 10 years from the establishment of the record.
(iv) Criteria and Procedures for a Market Trading Program. The plan must include the criteria and
procedures for conducting an annual evaluation of whether the milestone is achieved and, in
accordance with paragraph (d)(4)(v) of this section, for activating a market trading program in
the event the milestone is not achieved. A draft of the annual report evaluating whether the
milestone for each year is achieved shall be completed no later than 12 months from the end of
each milestone year. The plan must also provide for assessments of the program in the years
2013 and 2018.

40 CFR 51.309(d)(4)(iv) (enhanced display)

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40 CFR 51.309(d)(4)(v)

(v) Market trading program. The implementation plan must include requirements for a market
trading program to be implemented in the event that a milestone is not achieved. The plan shall
require that the market trading program be activated beginning no later than 15 months after
the end of the first year in which the milestone is not achieved. The plan shall also require that
sources comply, as soon as practicable, with the requirement to hold allowances covering their
emissions. Such market trading program must be sufficient to achieve the milestones in
paragraph (d)(4)(i) of this section, and must be consistent with the elements for such programs
outlined in § 51.308(e)(2)(vi). Such a program may include a geographic enhancement to the
program to address the requirement under § 51.302(b) related to reasonably attributable
impairment from the pollutants covered under the program.
(vi) Provision for the 2018 milestone.
(A) Unless and until a revised implementation plan is submitted in accordance with §
51.308(f) and approved by EPA, the implementation plan shall prohibit emissions from
covered stationary sources in any year beginning in 2018 that exceed the year 2018
milestone. In no event shall a market-based program approved under § 51.308(f) allow an
emissions cap for SO2 that is less stringent than the 2018 milestone, unless the
milestones are replaced by a different program approved by EPA as meeting the BART and
reasonable progress requirements established in § 51.308.
(B) The implementation plan must provide a framework, including financial penalties for
excess emissions based on the 2018 milestone, sufficient to ensure that the 2018
milestone will be met even if the implementation of the market trading program in
paragraph (d)(4)(v) of this section has not yet been triggered, or the source allowance
compliance provision of the trading program is not yet in effect.
(vii) Provisions for stationary source emissions of NOX and PM. The implementation plan must
contain any necessary long term strategies and BART requirements for stationary source PM
and NOX emissions. Any such BART provisions may be submitted pursuant to either §
51.308(e)(1) or '51.308(e)(2).
(5) Mobile sources. The plan submission must provide for:
(i)

Statewide inventories of onroad and nonroad mobile source emissions of VOC, NOX, SO2, PM2.5,
elemental carbon, and organic carbon for the years 2003, 2008, 2013, and 2018.
(A) The inventories must demonstrate a continuous decline in total mobile source emissions
(onroad plus nonroad; tailpipe and evaporative) of VOC, NOX, PM2.5, elemental carbon, and
organic carbon, evaluated separately. If the inventories show a continuous decline in total
mobile source emissions of each of these pollutants over the period 2003-2018, no further
action is required as part of this plan to address mobile source emissions of these
pollutants. If the inventories do not show a continuous decline in mobile source emissions
of one or more of these pollutants over the period 2003-2018, the plan submission must
provide for an implementation plan revision by no later than December 31, 2008
containing any necessary long-term strategies to achieve a continuous decline in total
mobile source emissions of the pollutant(s), to the extent practicable, considering
economic and technological reasonableness and federal preemption of vehicle standards
and fuel standards under title II of the CAA.

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40 CFR 51.309 (up to date as of 10/15/2024)
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40 CFR 51.309(d)(5)(i)(B)

(B) The plan submission must also provide for an implementation plan revision by no later
than December 31, 2008 containing any long-term strategies necessary to reduce
emissions of SO2 from nonroad mobile sources, consistent with the goal of reasonable
progress. In assessing the need for such long-term strategies, the State may consider
emissions reductions achieved or anticipated from any new Federal standards for sulfur in
nonroad diesel fuel.
(ii) Interim reports to EPA and the public in years 2003, 2008, 2013, and 2018 on the
implementation status of the regional and local strategies recommended by the Commission
Report to address mobile source emissions.
(6) Programs related to fire. The plan must provide for:
(i)

Documentation that all Federal, State, and private prescribed fire programs within the State
evaluate and address the degree visibility impairment from smoke in their planning and
application. In addition the plan must include smoke management programs that include all
necessary components including, but not limited to, actions to minimize emissions, evaluation
of smoke dispersion, alternatives to fire, public notification, air quality monitoring, surveillance
and enforcement, and program evaluation.

(ii) A statewide inventory and emissions tracking system (spatial and temporal) of VOC, NOX,
elemental and organic carbon, and fine particle emissions from fire. In reporting and tracking
emissions from fire from within the State, States may use information from regional datagathering and tracking initiatives.
(iii) Identification and removal wherever feasible of any administrative barriers to the use of
alternatives to burning in Federal, State, and private prescribed fire programs within the State.
(iv) Enhanced smoke management programs for fire that consider visibility effects, not only health
and nuisance objectives, and that are based on the criteria of efficiency, economics, law,
emission reduction opportunities, land management objectives, and reduction of visibility
impact.
(v) Establishment of annual emission goals for fire, excluding wildfire, that will minimize emission
increases from fire to the maximum extent feasible and that are established in cooperation with
States, tribes, Federal land management agencies, and private entities.
(7) Area sources of dust emissions from paved and unpaved roads. The plan must include an
assessment of the impact of dust emissions from paved and unpaved roads on visibility conditions
in the 16 Class I Areas. If such dust emissions are determined to be a significant contributor to
visibility impairment in the 16 Class I areas, the State must implement emissions management
strategies to address the impact as necessary and appropriate.
(8) Pollution prevention. The plan must provide for:
(i)

An initial summary of all pollution prevention programs currently in place, an inventory of all
renewable energy generation capacity and production in use, or planned as of the year 2002
(expressed in megawatts and megawatt-hours), the total energy generation capacity and
production for the State, the percent of the total that is renewable energy, and the State's
anticipated contribution toward the renewable energy goals for 2005 and 2015, as provided in
paragraph (d)(8)(vi) of this section.

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40 CFR 51.309(d)(8)(ii)

(ii) Programs to provide incentives that reward efforts that go beyond compliance and/or achieve
early compliance with air-pollution related requirements.
(iii) Programs to preserve and expand energy conservation efforts.
(iv) The identification of specific areas where renewable energy has the potential to supply power
where it is now lacking and where renewable energy is most cost-effective.
(v) Projections of the short- and long-term emissions reductions, visibility improvements, cost
savings, and secondary benefits associated with the renewable energy goals, energy efficiency
and pollution prevention activities.
(vi) A description of the programs relied on to achieve the State's contribution toward the
Commission's goal that renewable energy will comprise 10 percent of the regional power needs
by 2005 and 20 percent by 2015, and a demonstration of the progress toward achievement of
the renewable energy goals in the years 2003, 2008, 2013, and 2018. This description must
include documentation of the potential for renewable energy resources, the percentage of
renewable energy associated with new power generation projects implemented or planned, and
the renewable energy generation capacity and production in use and planned in the State. To
the extent that it is not feasible for a State to meet its contribution to the regional renewable
energy goals, the State must identify in the progress reports the measures implemented to
achieve its contribution and explain why meeting the State's contribution was not feasible.
(9) Implementation of additional recommendations. The plan must provide for implementation of all
other recommendations in the Commission report that can be practicably included as enforceable
emission limits, schedules of compliance, or other enforceable measures (including economic
incentives) to make reasonable progress toward remedying existing and preventing future regional
haze in the 16 Class I areas. The State must provide a report to EPA and the public in 2003, 2008,
2013, and 2018 on the progress toward developing and implementing policy or strategy options
recommended in the Commission Report.
(10) Periodic implementation plan revisions and progress reports. Each Transport Region State must
submit to the Administrator periodic reports in the years 2013 and as specified for subsequent
progress reports in § 51.308(g). The progress report due in 2013 must be in the form of an
implementation plan revision that complies with the procedural requirements of §§ 51.102 and
51.103.
(i)

The report due in 2013 will assess the area for reasonable progress as provided in this section
for mandatory Class I Federal area(s) located within the State and for mandatory Class I
Federal area(s) located outside the State that may be affected by emissions from within the
State. This demonstration may be based on assessments conducted by the States and/or a
regional planning body. The progress report due in 2013 must contain at a minimum the
following elements:
(A) A description of the status of implementation of all measures included in the
implementation plan for achieving reasonable progress goals for mandatory Class I
Federal areas both within and outside the State.
(B) A summary of the emissions reductions achieved throughout the State through
implementation of the measures described in paragraph (d)(10)(i)(A) of this section.

40 CFR 51.309(d)(10)(i)(B) (enhanced display)

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40 CFR 51.309 (up to date as of 10/15/2024)
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40 CFR 51.309(d)(10)(i)(C)

(C) For each mandatory Class I Federal area within the State, an assessment of the following:
the current visibility conditions for the most impaired and least impaired days; the
difference between current visibility conditions for the most impaired and least impaired
days and baseline visibility conditions; the change in visibility impairment for the most
impaired and least impaired days over the past 5 years.
(D) An analysis tracking the change over the past 5 years in emissions of pollutants
contributing to visibility impairment from all sources and activities within the State.
Emissions changes should be identified by type of source or activity. The analysis must be
based on the most recent updated emissions inventory, with estimates projected forward
as necessary and appropriate, to account for emissions changes during the applicable
5-year period.
(E) An assessment of any significant changes in anthropogenic emissions within or outside
the State that have occurred over the past 5 years that have limited or impeded progress
in reducing pollutant emissions and improving visibility.
(F) An assessment of whether the current implementation plan elements and strategies are
sufficient to enable the State, or other States with mandatory Federal Class I areas
affected by emissions from the State, to meet all established reasonable progress goals.
(G) A review of the State's visibility monitoring strategy and any modifications to the strategy
as necessary.
(ii) At the same time the State is required to submit the 5-year progress report due in 2013 to EPA
in accordance with paragraph (d)(10)(i) of this section, the State must also take one of the
following actions based upon the information presented in the progress report:
(A) If the State determines that the existing implementation plan requires no further
substantive revision at this time in order to achieve established goals for visibility
improvement and emissions reductions, the State must provide to the Administrator a
negative declaration that further revision of the existing implementation plan is not
needed at this time.
(B) If the State determines that the implementation plan is or may be inadequate to ensure
reasonable progress due to emissions from sources in another State(s) which participated
in a regional planning process, the State must provide notification to the Administrator and
to the other State(s) which participated in the regional planning process with the States.
The State must also collaborate with the other State(s) through the regional planning
process for the purpose of developing additional strategies to address the plan's
deficiencies.
(C) Where the State determines that the implementation plan is or may be inadequate to
ensure reasonable progress due to emissions from sources in another country, the State
shall provide notification, along with available information, to the Administrator.
(D) Where the State determines that the implementation plan is or may be inadequate to
ensure reasonable progress due to emissions from within the State, the State shall
develop additional strategies to address the plan deficiencies and revise the
implementation plan no later than one year from the date that the progress report was
due.

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40 CFR 51.309(d)(10)(iii)

(iii) The requirements of § 51.308(g) regarding requirements for periodic reports describing
progress towards the reasonable progress goals apply to States submitting plans under this
section, with respect to subsequent progress reports due after 2013.
(iv) The requirements of § 51.308(h) regarding determinations of the adequacy of existing
implementation plans apply to States submitting plans under this section, with respect to
subsequent progress reports due after 2013.
(11) State planning and interstate coordination. In complying with the requirements of this section, States
may include emission reductions strategies that are based on coordinated implementation with
other States. Examples of these strategies include economic incentive programs and transboundary
emissions trading programs. The implementation plan must include documentation of the technical
and policy basis for the individual State apportionment (or the procedures for apportionment
throughout the trans-boundary region), the contribution addressed by the State's plan, how it
coordinates with other State plans, and compliance with any other appropriate implementation plan
approvability criteria. States may rely on the relevant technical, policy and other analyses developed
by a regional entity (such as the Western Regional Air Partnership) in providing such documentation.
Conversely, States may elect to develop their own programs without relying on work products from a
regional entity.
(12) Tribal implementation. Consistent with 40 CFR Part 49, tribes within the Transport Region may
implement the required visibility programs for the 16 Class I areas, in the same manner as States,
regardless of whether such tribes have participated as members of a visibility transport
commission.
(e) States electing not to implement the commission recommendations. Any Transport Region State may elect
not to implement the Commission recommendations set forth in paragraph (d) of this section. Such
States are required to comply with the timelines and requirements of § 51.308. Any Transport Region
State electing not to implement the Commission recommendations must advise the other States in the
Transport Region of the nature of the program and the effect of the program on visibility-impairing
emissions, so that other States can take this information into account in developing programs under this
section.
(f) [Reserved]
(g) Additional Class I areas. Each Transport Region State implementing the provisions of this section as the
basis for demonstrating reasonable progress for mandatory Class I Federal areas other than the 16 Class
I areas must include the following provisions in its implementation plan. If a Transport Region State
submits an implementation plan which is approved by EPA as meeting the requirements of this section, it
will be deemed to comply with the requirements for reasonable progress for the period from approval of
the plan to 2018.
(1) A demonstration of expected visibility conditions for the most impaired and least impaired days at
the additional mandatory Class I Federal area(s) based on emissions projections from the long-term
strategies in the implementation plan. This demonstration may be based on assessments conducted
by the States and/or a regional planning body.
(2) Provisions establishing reasonable progress goals and implementing any additional measures
necessary to demonstrate reasonable progress for the additional mandatory Federal Class I areas.
These provisions must comply with the provisions of § 51.308(d)(1) through (4).

40 CFR 51.309(g)(2) (enhanced display)

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(i)

40 CFR 51.309(g)(2)(i)

In developing long-term strategies pursuant to § 51.308(d)(3), the State may build upon the
strategies implemented under paragraph (d) of this section, and take full credit for the visibility
improvement achieved through these strategies.

(ii) The requirement under § 51.308(e) related to Best Available Retrofit Technology for regional
haze is deemed to be satisfied for pollutants addressed by the milestones and backstop trading
program if, in establishing the emission reductions milestones under paragraph (d)(4) of this
section, it is shown that greater reasonable progress will be achieved for these additional Class
I areas than would be achieved through the application of source-specific BART emission
limitations under § 51.308(e)(1).
(iii) The Transport Region State may consider whether any strategies necessary to achieve the
reasonable progress goals required by paragraph (g)(2) of this section are incompatible with
the strategies implemented under paragraph (d) of this section to the extent the State
adequately demonstrates that the incompatibility is related to the costs of the compliance, the
time necessary for compliance, the energy and nonair quality environmental impacts of
compliance, or the remaining useful life of any existing source subject to such requirements.
[64 FR 35769, July 1, 1999, as amended at 68 FR 33784, June 5, 2003; 68 FR 39846, July 3, 2003; 68 FR 61369, Oct. 28, 2003; 68
FR 71014, Dec. 22, 2003; 71 FR 60632, Oct. 13, 2006; 82 FR 3128, Jan. 10, 2017]

40 CFR 51.309(g)(2)(iii) (enhanced display)

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