[Federal Register Volume 70, Number 94 (Tuesday, May 17, 2005)]
[Proposed Rules]
[Pages 28239-28252]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-9724]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 52
[RME Docket Number R08-OAR-2005-CO-0001; FRL-7912-9]
Approval and Promulgation of Air Quality Implementation Plans;
State of Colorado; Denver Early Action Compact Ozone Plan, Attainment
Demonstration of the 8-hour Ozone Standard, and Approval of Related
Revisions
AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.
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SUMMARY: EPA is proposing approval of a State Implementation Plan (SIP)
revision submitted by the State of Colorado. On July 21, 2004, the
Governor of Colorado submitted an Early Action Compact (EAC) ozone plan
[[Page 28240]]
for the Denver metropolitan area (hereafter, Denver area) for the 8-
hour ozone National Ambient Air Quality Standard (NAAQS). The
Governor's submittal also contained an attainment demonstration for the
8-hour ozone NAAQS. In conjunction with the EAC ozone plan, the
Governor submitted revisions to Colorado's Common Provisions
Regulation, Colorado's Regulation No. 7 ``Emissions of Volatile Organic
Compounds'' (hereafter, Regulation No. 7), and revisions to Colorado's
Regulation No. 11 ``Motor Vehicle Emissions Inspection Program''
(hereafter Regulation No. 11). In this action, EPA is proposing
approval of the Denver EAC ozone plan, the associated attainment
demonstration, and the revisions to the Common Provisions Regulation,
Regulation No. 7, and Regulation No. 11. This action is being taken
under section 110 of the Clean Air Act.
DATES: Comments must be received on or before June 16, 2005.
ADDRESSES: Submit your comments, identified by RME Docket Number R08-
OAR-2005-CO-0001, by one of the following methods:
Federal eRulemaking Portal: http://www.regulations.gov.
Follow the on-line instructions for submitting comments.
Agency Web site: http://docket.epa.gov/rmepub/index.jsp.
Regional Materials in EDOCKET (RME), EPA's electronic public docket and
comment system for regional actions, is EPA's preferred method for
receiving comments. Follow the on-line instructions for submitting
comments.
E-mail: [email protected] and [email protected].
Fax: (303) 312-6064 (please alert the individual listed in
the FOR FURTHER INFORMATION CONTACT if you are faxing comments).
Mail: Richard R. Long, Director, Air and Radiation
Program, Environmental Protection Agency (EPA), Region 8, Mailcode 8P-
AR, 999 18th Street, Suite 300, Denver, Colorado 80202-2466.
Hand Delivery: Richard R. Long, Director, Air and
Radiation Program, Environmental Protection Agency (EPA), Region 8,
Mailcode 8P-AR, 999 18th Street, Suite 300, Denver, Colorado 80202-
2466. Such deliveries are only accepted Monday through Friday, 8:00
a.m. to 4:55 p.m., excluding federal holidays. Special arrangements
should be made for deliveries of boxed information.
Instructions: Direct your comments to RME Docket Number R08-OAR-
2005-CO-0001. EPA's policy is that all comments received will be
included in the public docket without change and may be made available
at http://docket.epa.gov/rmepub/index.jsp, 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 EDOCKET,
regulations.gov, or e-mail. EPA's Regional Materials in EDOCKET and
federal regulations.gov Web site are ``anonymous access'' systems,
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 EDOCKET or
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. For
additional information about EPA's public docket visit EDOCKET online
or see the Federal Register of May 31, 2002 (67 FR 38102). For
additional instructions on submitting comments, go to Section I.
General Information of the SUPPLEMENTARY INFORMATION section of this
document.
Docket: All documents in the docket are listed in the Regional
Materials in EDOCKET index at http://docket.epa.gov/rmepub/index.jsp.
Although listed in the index, some information is not publicly
available, i.e., 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 publically
available only in hard copy form. Publicly available docket materials
are available either electronically in Regional Materials in EDOCKET or
in hard copy at the Air and Radiation Program, Environmental Protection
Agency (EPA), Region 8, 999 18th Street, Suite 300, Denver, Colorado
80202-2466. 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 a.m. to 4 p.m., excluding federal
holidays.
FOR FURTHER INFORMATION CONTACT: Tim Russ, Air and Radiation Program,
Environmental Protection Agency (EPA), Region 8, Mailcode 8P-AR, 999
18th Street, Suite 300, Denver, Colorado 80202-2466, phone (303) 312-
6479, and e-mail at: [email protected].
SUPPLEMENTARY INFORMATION:
Table of Contents
I. General Information
II. What is the purpose of this action?
III. What is the State's process to submit these materials to EPA?
IV. Background for Early Action Compacts for the 8-hour Ozone NAAQS
V. EPA's evaluation of the Denver Early Action Compact Milestone
Submittals
VI. EPA's evaluation of the Denver Early Action Compact Ozone Plan
VII. EPA's evaluation of the Denver Early Action Compact Ozone
Plan's Attainment Demonstration
VIII. EPA's evaluation of the Regulation No. 7 Revisions
IX. EPA's evaluation of the Regulation No. 11 Revisions
X. EPA's evaluation of the Common Provisions Regulation Revision
XI. Consideration of Section 110(l) of the CAA
XII. Proposed Action
XIII. Statutory and Executive Order Reviews
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.
(ii) The words EPA, we, us or our mean or refer to the United
States Environmental Protection Agency.
(iii) The initials NAAQS mean National Ambient Air Quality
Standard.
(iv) The initials SIP mean or refer to State Implementation Plan.
(v) The word State means the State of Colorado, unless the context
indicates otherwise.
I. General Information
A. What Should I Consider as I Prepare My Comments for EPA?
1. Submitting CBI. Do not submit this information to EPA through
regulations.gov or e-mail. Clearly mark the part or all of the
information that you claim to be CBI. For CBI information in a disk or
CD ROM that you mail to EPA, mark the outside of the disk or CD ROM as
CBI and then identify electronically within the disk or CD ROM the
specific information that is claimed as CBI. In addition to one
complete version of the comment that
[[Page 28241]]
includes information claimed as CBI, a copy of the comment that does
not contain the information claimed as CBI must be submitted for
inclusion in the public docket. Information so marked will not be
disclosed except in accordance with procedures set forth in 40 CFR part
2.
2. Tips for Preparing Your Comments. When submitting comments,
remember to:
I. Identify the rulemaking by docket number and other identifying
information (subject heading, Federal Register date and page number).
II. Follow directions--The agency may ask you to respond to
specific questions or organize comments by referencing a Code of
Federal Regulations (CFR) part or section number.
III. Explain why you agree or disagree; suggest alternatives and
substitute language for your requested changes.
IV. Describe any assumptions and provide any technical information
and/or data that you used.
V. If you estimate potential costs or burdens, explain how you
arrived at your estimate in sufficient detail to allow for it to be
reproduced.
VI. Provide specific examples to illustrate your concerns, and
suggest alternatives.
VII. Explain your views as clearly as possible, avoiding the use of
profanity or personal threats.
VIII. Make sure to submit your comments by the comment period
deadline identified.
II. What Is the Purpose of This Action?
In this action, we are proposing approval of the Early Action
Compact ozone plan for the Denver area that is designed to demonstrate
attainment of the 8-hour ozone NAAQS by December 31, 2007 with
additional provisions for continued maintenance of the ozone NAAQS
through 2012, we're proposing approval of the photochemical modeled
attainment demonstration, we're proposing approval of certain revisions
to the State's Common Provisions Regulation, we're proposing approval
of revisions to Regulation No. 7 for the control of VOC and
NOX emissions from certain oil and gas exploration and
production operations, we're proposing approval of revisions to the
motor vehicle inspections and maintenance (I/M) requirements in
Regulation No. 11 the Governor submitted on July 21, 2004, and we're
proposing approval of several prior I/M revisions to Regulation No. 11.
III. What Is the State's Process to Submit These Materials to EPA?
Section 110(k) of the CAA addresses our actions on submissions of
revisions to a SIP. The CAA requires States to observe certain
procedural requirements in developing SIP revisions for submittal to
us. Section 110(a)(2) of the CAA requires that each SIP revision be
adopted after reasonable notice and public hearing. This must occur
prior to the revision being submitted by a State to us.
A. The Colorado Air Quality Control Commission (AQCC) held a public
hearing for the Denver EAC ozone plan on March 11 and 12, 2004. The
AQCC adopted the EAC ozone plan, and its associated attainment
demonstration, directly after the hearing. This SIP revision became
State effective on May 30, 2004, and was submitted by the Governor to
us on July 21, 2004.
We have evaluated the Governor's submittal for the Denver EAC ozone
plan and have determined that the State met the requirements for
reasonable notice and public hearing under section 110(a)(2) of the
CAA. By operation of law under section 110(k)(1)(B) of the CAA, the
Governor's July 21, 2004, submittal became complete on January 21,
2005.
B. The Colorado AQCC held a public hearing for the revisions to the
Common Provisions Regulation, Regulation No. 7 and Regulation No. 11 on
March 11 and 12, 2004. The AQCC adopted these revisions directly after
the hearing. These SIP revisions became State effective on May 30,
2004, and were submitted by the Governor to us on July 21, 2004.
We have evaluated the Governor's submittal for the Common
Provisions Regulation, Regulation No. 7 and Regulation No. 11 revisions
and have determined that the State met the requirements for reasonable
notice and public hearing under section 110(a)(2) of the CAA. By
operation of law under section 110(k)(1)(B) of the CAA, the Governor's
July 21, 2004, submittal became complete on January 21, 2005.
C. For the 2000, 2001, and 2002 Regulation No. 11 revisions, the
Colorado AQCC held a public hearing on November 16, 2000, December 20,
2001, August 15, 2002, and October 17, 2002. The AQCC adopted the
revisions to Regulation No. 11 directly after these hearings. These SIP
revisions became State effective on December 30, 2000, January 30,
2002, September 30, 2002, and December 30, 2002, respectively, and were
all submitted by the Governor to us on June 20, 2003.
We evaluated the Governor's submittal and concluded that the State
met the requirements for reasonable notice and public hearing under
section 110(a)(2) of the CAA. Pursuant to section 110(k)(1)(B) of the
CAA, we reviewed these SIP materials for conformance with the
completeness criteria in 40 CFR part 51, appendix V and determined that
the Governor's June 30, 2003, submittal was administratively and
technically complete. Our completeness determination was sent on
November 28, 2003, through a letter from Robert E. Roberts, Regional
Administrator, to Governor Bill Owens.
D. For the 2003 Regulation No. 11 revisions, the Colorado AQCC held
a public hearing on September 18, 2003, and December 18, 2003. The AQCC
adopted the revisions to Regulation No. 11 directly after these
hearings. These SIP revisions became State effective on November 30,
2003, and March 1, 2004, respectively, and were all submitted by the
Governor to us on April 12, 2004.
We evaluated the Governor's submittal and concluded that the State
met the requirements for reasonable notice and public hearing under
section 110(a)(2) of the CAA. Pursuant to section 110(k)(1)(B) of the
CAA, we reviewed these SIP materials for conformance with the
completeness criteria in 40 CFR part 51, appendix V and determined that
the Governor's April 12, 2004, submittal was administratively and
technically complete. Our completeness determination was sent on June
17, 2004, through a letter from Robert E. Roberts, Regional
Administrator, to Governor Bill Owens.
E. The Colorado AQCC held a public hearing for additional revisions
to Regulation No. 7 on December 16, 2004. The AQCC adopted these
revisions directly after the hearing. These SIP revisions became State
effective on March 2, 2005, and were submitted by the Governor to us on
March 24, 2005.
We have evaluated the Governor's submittal of the additional
revisions to Regulation No. 7 and have determined that the State met
the requirements for reasonable notice and public hearing under section
110(a)(2) of the CAA. Pursuant to section 110(k)(1)(B) of the CAA, we
reviewed these SIP materials for conformance with the completeness
criteria in 40 CFR part 51, appendix V and determined that the
Governor's March 24, 2005, submittal was administratively and
technically complete. Our completeness determination was sent on April
6, 2005, through a letter from Robert E. Roberts, Regional
Administrator, to Governor Bill Owens.
[[Page 28242]]
IV. Background for Early Action Compacts for the 8-hour Ozone NAAQS
A. Why Was the Compact Program Developed?
As discussed in our proposed rule for the implementation of the 8-
hour ozone NAAQS (see 68 FR 32805, June 2, 2003), State, local and
Tribal air pollution control agencies continued to express a need for
added flexibility in implementing the 8-hour ozone NAAQS, including
incentives for taking action sooner than the CAA requires for reducing
ground-level ozone. The compact program permits local areas to make
decisions that will achieve reductions in VOC and NOX
emissions sooner than otherwise is mandated by the CAA. Early planning
and early implementation of control measures that improves air quality
will likely accelerate protection of public health. We issued our
initial policy on early planning on November 14, 2002 \1\ (hereafter,
November 14, 2002 policy), with a further description in our June 2,
2003 proposed rule (68 FR 32805), and as provided in our April 30, 2004
final rule (69 FR 23951) entitled ``Final Rule To Implement the 8-Hour
Ozone National Ambient Air Quality Standard--Phase 1.''
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\1\ Memorandum from Jeffrey R. Holmstead, Assistant
Administrator, to Regional Administrators, entitled ``Schedule for
8-Hour Ozone Designations and its Effect on Early Action Compacts''
dated November 14, 2002.
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B. What Was the ``Early Action'' Protocol That Texas Submitted to EPA?
In March of 2002, the Texas Commission on Environmental Quality
(TCEQ) encouraged EPA to consider incentives for early planning towards
achieving the 8-hour ozone NAAQS. The TCEQ submitted to EPA the
Protocol for Early Action Compacts Designed to Achieve and Maintain the
8-hour Ozone Standard (Protocol). The Protocol was designed to achieve
NOX and VOC emissions reductions for the 8-hour ozone NAAQS
sooner than would otherwise be required under the CAA. The TCEQ
recommended that the Protocol be formalized by ``Early Action Compact''
agreements primarily developed by local, State and Federal (EPA)
officials. In a letter dated June 19, 2002, from Gregg Cooke,
Administrator, Region 6, to Robert Huston, Chairman, TCEQ, EPA endorsed
the principles outlined in the Protocol. The Protocol was subsequently
revised on December 11, 2002, \2\ based on comments from EPA. Areas
meeting the necessary prerequisites prepared an Early Action Compact
(EAC) document that was based on the provisions of the Protocol. These
EACs were then executed by the necessary State and local entities,
along with the respective EPA Regional Office, by December 31, 2002.
The EACs were required to contain the following:
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\2\ The Texas Protocol was submitted to EPA in March 2002 for
review and was revised in December 2002 based on the Agency's
comments concerning the need for additional milestones and other
clarifications. Docket No. OAR-2003-0090-0004.
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1. Early planning, implementation, and emissions reductions leading
to expeditious attainment and maintenance of the 8-hour ozone standard.
2. Local control of the measures employed with broad-based public
input.
3. State support to ensure technical integrity of the early action
plan including completion of emissions inventories and dispersion
modeling (based on most recent Agency guidance) to support the
attainment demonstration and selected local control measures.
4. Formal incorporation of the early action plan itself into the
State Implementation Plan (SIP). Also, adoption and submittal as
revisions to the SIP of control strategies that demonstrate attainment.
5. Completion of a component to address emissions growth at least 5
years beyond December 31, 2007, ensuring that the area will remain in
attainment of the 8-hour ozone standard during that period.
6. Semiannual reports detailing progress toward completion of
compact milestones.
7. Designation of all areas as attainment or nonattainment in April
2004, but for compact areas, deferral of the effective date of the
nonattainment designation and/or designation requirements so long as
all compact terms and milestones continue to be met.
8. Safeguards to return areas to traditional SIP attainment
requirements should compact terms be unfulfilled (e.g., if the area
fails to attain in 2007), with appropriate credit given for reduction
measures already implemented.
C. What are the milestone and submittal requirements for Early Action
Compact areas?
The November 14, 2002, policy memorandum, an additional EPA
memorandum dated April 4, 2003, \3\ our June 2, 2003 proposed rule (68
FR 32805), and our April 30, 2004 final rule (69 FR 23951) establish
the activities EAC areas are required to perform and the necessary
submittals that must be made to EPA. EAC areas are required to select
control strategies based on SIP-quality dispersion modeling that shows
attainment of the 8-hour ozone NAAQS no later than December 31, 2007
through implementation of the control strategies. We specified that all
EAC areas must submit a local plan by March 31, 2004 that includes
measures that are specific, quantified, and permanent and that, once
approved into the SIP by EPA, will be federally enforceable. The March
31, 2004 submission also had to include specific implementation dates
for the local controls, as well as detailed documentation supporting
the selection of measures. Control measures must be implemented no
later than December 31, 2005, which is at least 16\1/2\ months earlier
than required by the CAA. Reports are required every 6 months to
describe progress toward completion of milestones.
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\3\ Memorandum from Lydia N. Wegman, Director, Air Quality
Strategies and Standards Division, ``Early Action Compacts (EACs):
The June 16, 2003 Submission and Other Clarifications,'' April 4,
2003. Docket No. OAR-2003-0090-0002.
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Table IV-1 below presents the milestones and submissions that EAC
areas are required to complete in order to continue eligibility for a
deferral of the effective date of the nonattainment designation for the
8-hour ozone NAAQS.
Table IV-1.--Early Action Compact Milestones
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Submittal Date Compact Milestone
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December 31, 2002...................... State/Locals submit EAC for EPA
signature.
June 16, 2003.......................... State/Locals submit preliminary
list and description of
potential local control
measures under consideration.
March 31, 2004......................... Plan submitted to State for
necessary action (includes
specific, quantified and
permanent control measures to
be adopted).
December 31, 2004...................... State submits EAC plan and
adopted local measures to EPA
as a SIP revision that, when
approved, will be federally
enforceable.
No later than December 31, 2005........ State/Locals to implement
adopted SIP control measures.
June 30, 2006.......................... State reports on implementation
of control measures,
assessment of air quality
improvement, and reductions in
NOX and VOC emissions to date.
December 31, 2007...................... EAC area attains 8-hour ozone
NAAQS.
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In accordance with the Protocol and the executed EAC documents, EPA
[[Page 28243]]
recognized the EAC areas' commitments to early, voluntary action by
designating the EAC areas that were violating the 8-hour NAAQS (based
on air quality data from 2001, 2002, and 2003) as nonattainment on
April 30, 2004 (see 69 FR 23858), but deferred the effective date of
the nonattainment designation so long as all terms and milestones of
the EAC continue to be met.
V. EPA's Evaluation of the Denver Early Action Compact Milestone
Submittals
We have reviewed the Denver EAC milestone submittals with respect
to the requirements in the Protocol and the executed December 31, 2002
Denver EAC. We consider these milestone submittals as necessary
prerequisites in order for us to propose approval of the Denver EAC
ozone plan SIP revision. The following are our analyses of how the EAC
milestone submittal requirements, discussed above, have been met for
the Denver EAC.
A. State/Locals Submit EAC for EPA Signature by December 31, 2002
The State of Colorado delivered the Denver EAC to EPA, Region 8 on
December 30, 2002. The EAC had been signed by Jim Scherer, Chairman of
the Denver Regional Air Quality Council (RAQC), Robert E. Brady Jr.,
Chairman of the Colorado Air Quality Control Commission (AQCC), Douglas
H. Benevento, Executive Director, Colorado Department of Public Health
and Environment (CDPHE), Thomas Norton, Executive Director, Colorado
Department of Transportation (CDOT), and Sharon L. Richardson,
Chairman, Denver Regional Council of Governments (DRCOG). The Denver
EAC was executed by Robert E. Roberts, Regional Administrator, EPA
Region 8, on December 31, 2002.
The Denver EAC was amended on March 18, 2004 with the additional
signatures of Stephen F. Stutz, Chair, Elbert County Board of County
Commissioners, Kathay Rennels, Chair, Larimer County Board of County
Commissioners, Michael Harms, Chair, Morgan County Board of County
Commissioners, and Rob Masden, Chair, Weld County Board of County
Commissioners.
Based on the above actions, EPA has determined that this EAC
milestone requirement has been addressed.
B. State/Locals Submit Preliminary List and Description of Potential
Local Control Measures Under Consideration by June 16, 2003
On June 16, 2003, Ken Lloyd, Executive Director, RAQC and Margie
Perkins, Director, Air Pollution Control Division (APCD) of the CDPHE
jointly submitted the Denver EAC area's ``June 16, 2003 Milestone--
Identification and Description of Potential Control Strategies for
Further Consideration.'' This submittal contained a further description
of the stakeholder process, strategy evaluation considerations, and a
list of ten potential emission reduction strategies. Provided for each
of the potential strategies were, a brief description, estimate of
potential emission reductions (where available), an implementation
approach and schedule, and a description of the geographic area of
application of the strategy.
Based on the content of this document, EPA has determined that this
EAC milestone requirement has been addressed.
C. Plan Submitted to State for necessary Action (Includes Specific,
Quantified and Permanent Control Measures To Be Adopted) by March 31,
2004
The Denver RAQC held a public meeting on December 11, 2003, at the
end of which, the RAQC gave their approval to the Denver EAC ozone
plan. In conjunction with the RAQC's planning processes, the Colorado
AQCC entertained public comment during noticed public meetings in July,
August, September, November, and December, 2003. With the RAQC's
approval, the Denver EAC plan, and associated materials, were then
transmitted to the Colorado AQCC. At their December 18, 2003, public
meeting the AQCC gave notice to open a three-month public comment
period and scheduled a public hearing for March 11, 2004 (which was
subsequently extended to March 11 and March 12, 2004.) At the December
18, 2003 AQCC meeting, the AQCC also noticed for public comment
revisions to the appropriate Colorado Regulations that would achieve
the necessary emission reductions that were modeled in the attainment
demonstration which supported the EAC plan. Once approved, these
Regulation revisions would generate permanent and enforceable emission
reductions. We note that the Denver EAC plan does not take any credit
for voluntary measures.
Based on the above actions, EPA has determined that this EAC
milestone requirement has been addressed.
D. State Submits EAC Plan and Adopted Local Measures to EPA as a SIP
Revision (That, When Approved, Will Be Federally Enforceable) by
December 31, 2004
On March 11 and March 12, 2004, the AQCC conducted a public hearing
to consider the Denver EAC plan, the attainment demonstration, and the
necessary revisions to Colorado's Common Provisions Regulation,
Regulation No. 7, and Regulation No. 11. At the end of the public
hearing on March 12, 2004, the AQCC adopted all the above SIP
materials. The entire Denver EAC SIP package was forwarded to Governor
Owens who then transmitted the SIP package to EPA, Region 8, with a
letter dated July 21, 2004.
We note that on March 10, 2004, and just prior to the AQCC public
hearing of March 11 and March 12, 2004, we sent a letter to the State
and AQCC expressing concerns with the adequacy of the revisions to
Colorado's Regulation No. 7. In that March 10, 2004 letter, we stated
that we would continue to work with the State to resolve our concerns.
CDPHE and EPA staff met several times starting in August, 2004 up
through December, 2004 to address the Regulation No. 7 deficiencies. At
the September, 2004 AQCC meeting, the AQCC established a public comment
period and noticed for public hearing revisions to Regulation No. 7.
The AQCC held a public hearing on December 16, 2004 to consider the
revisions to Regulation No. 7. The AQCC adopted the revisions directly
after the public hearing and Governor Owens submitted these
supplemental Regulation No. 7 revisions to us on March 24, 2005.
Based on the above actions, EPA has determined that this EAC
milestone requirement has been addressed.
We also note that in addition to meeting all the required EAC
milestones, the State and RAQC jointly submitted ``Progress Reports''
on June 30, 2003, December 31, 2003, March 31, 2004, and December 31,
2004.
VI. EPA's Evaluation of the Denver Early Action Compact Ozone Plan
We have reviewed the Denver EAC ozone plan (hereafter, Denver EAC
plan) with respect to the requirements in the Protocol, the December
31, 2002 Denver EAC document, and our general requirements for a
nonattainment area plan and believe that approval of the Denver EAC
plan is warranted. The following are our descriptions and analysis of
how the Denver EAC plan meets the necessary provisions referenced
above.
We note that the Denver EAC plan is divided into two sections; a
non-SIP introduction and monitoring background section and the SIP
section entitled ``8-Hour Ozone State Implementation Plan'' that
contains emission inventories, control measures,
[[Page 28244]]
photochemical dispersion modeling, and a weight of evidence analysis.
A. Introduction and Monitoring Background Section (non-SIP Materials)
The introduction section discusses the EAC protocol, the aspects of
the Denver EAC, the Protocol milestones and how these were met,
information that went into the development of the SIP emission
inventories and dispersion modeling, emission reduction strategies,
aspects of maintenance for growth, a brief description of the
stakeholder/public process, and a description of the area encompassed
by the Denver EAC plan. The ozone monitoring section provides
information with respect to the location of Front Range ozone monitors
(from southern metropolitan Denver north to Fort Collins including
Rocky Mountain National Park), the State's ambient air quality data
assurance program, a description and commitment for continued operation
of the ozone monitoring network, and relevant 8-hour ozone monitoring
data from 1996 through 2003 with design values presented for data from
2001, 2002, and 2003.
B. Denver EAC Plan--``8-Hour Ozone State Implementation Plan'
1. Base Case Emissions Inventories
(a) As described in Chapter I of the Denver EAC plan, the State and
RAQC used demographic data that was provided by the metropolitan
planning organizations (MPO), DRCOG and North Front Range
Transportation and Air Quality Planning Council (NFRTAQPC). Demographic
data were prepared for 2002, 2007, and 2012 and are presented in Table
4 of the Denver EAC plan.
(b) At the time that the emission inventories were being prepared
for the Denver EAC plan, EPA had not yet finalized the 8-hour ozone
nonattainment boundary for the Denver-Boulder-Greeley area \4\. The
State and RAQC prepared the EAC emission inventories for two situations
depending on EPA's final decision on the boundary: (1) inventories
based on Adams, Arapahoe, Boulder, Broomfield, Denver, Douglas,
Jefferson, and Weld Counties, and (2) inventories based on Adams,
Arapahoe, Boulder, Broomfield, Denver, Douglas, Elbert, Jefferson,
Larimer, Morgan, and Weld Counties. These inventories address ozone
precursor emissions of volatile organic compounds (VOC) and nitrogen
oxides (NOX).
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\4\ EPA promulgated the final 8-hour ozone nonattainment
boundary for the Denver-Boulder-Greeley area on April 30, 2004 (see
69 FR 23858.) The boundary includes all of Adams, Arapahoe, Boulder,
Broomfield, Denver, Douglas, and Jefferson Counties and the southern
halves of Larimer and Weld Counties.
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(c) The 2002 and 2007 base case inventories incorporate control
measures that were in place in 2002 and were predicted to be in place
in 2007. The essential control measures are described in Chapter I of
the Denver EAC plan and are: (1) Federally-mandated regulations for
motor vehicle exhaust (or tailpipe) emissions and Federally-mandated
regulations for exhaust emissions from non-road engines, (2) Colorado's
Regulation No. 7 for the control of VOC emissions, and (3) Colorado's
Regulation No. 11, the State's Automobile Inspection and Readjustment
(A.I.R.) Program, which requires the application of the State's Basic
Inspection and Maintenance (I/M) program for vehicles older than 1982
and the Enhanced I/M program for vehicles of model year 1982 and newer.
With respect to the Basic I/M program, Chapter I, 2 of the EAC plan
states, ``The computer modeling does not include any credit for the
basic programs in Colorado Springs and Fort Collins/Greeley areas and
such basic programs are not part of, or being submitted for inclusion
in, the SIP.'' In addition to the above, Chapter I, 4 indicates that a
conventional gasoline Reid Vapor Pressure (RVP) of 8.2 pounds per
square inch (psi) was used in the 2002 base case inventory and an RVP
of 9.0 was assumed for the 2007 base case inventory. Chapter I.,4 also
states that ``All of the inventories were developed using EPA-approved
emissions modeling methods, including EPA's MOBILE6 model and local VMT
data for on-road mobile source emissions, EPA's non-road model and
local demographic information for area and off-road sources, and
reported actual emissions for point sources.'' The 2002 and 2007 base
case VOC and NOX emission inventories are presented in Table
5a and Table 5b in Chapter I of the Denver EAC plan and are summarized
below in Tables VI-1 and VI-2.
Table VI-1.--Summary of Emission Inventories in Tons Per Day (TPD) Adams, Arapahoe, Boulder, Broomfield, Denver,
Douglas, Jefferson, and Weld Counties
----------------------------------------------------------------------------------------------------------------
Source category 2002 VOCs 2002 NOX 2007 VOCs 2007 NOX
----------------------------------------------------------------------------------------------------------------
Point Sources............................................... 192.8 105.2 204.1 107.1
Area Sources................................................ 96.9 25.6 104.1 27.6
Non-Road Sources............................................ 73.1 87.99 53.7 82.5
On-Road Sources............................................. 152.8 157.8 117.5 119.3
Subtotal Anthropogenic...................................... 515.6 376.6 479.4 336.5
Biogenics................................................... 468.1 37.1 468.1 37.1
--------------
Total................................................... 983.7 413.7 947.5 373.6
----------------------------------------------------------------------------------------------------------------
Table VI-2.--Summary of Emission Inventories in Tons Per Day (TPD) Adams, Arapahoe, Boulder, Broomfield, Denver,
Douglas, Elbert, Jefferson, Larimer, Morgan, and Weld Counties
----------------------------------------------------------------------------------------------------------------
Source category 2002 VOCs 2002 NOX 2007 VOCs 2007 NOX
----------------------------------------------------------------------------------------------------------------
Point Sources............................................... 200.0 140.1 209.3 144.9
Area Sources................................................ 111.3 30.4 119.6 32.7
Non-Road Sources............................................ 84.9 104.6 62.6 92.4
On-Road Sources............................................. 172.6 177.6 135.1 136.6
Subtotal Anthropogenic...................................... 568.8 452.7 526.6 406.6
Biogenics................................................... 799.46 52.3 799.5 52.3
--------------
[[Page 28245]]
Total................................................... 1368.3 505.0 1326.1 458.9
----------------------------------------------------------------------------------------------------------------
2. Control Measures
Chapter II of the Denver EAC plan describes the additional control
measures, above and beyond those assumed in the 2007 base case
emissions inventory, that will be implemented by December 31, 2005.
These additional control measures are incorporated into the SIP to
demonstrate attainment of the 8-hour ozone NAAQS by 2007, maintenance
of the 8-hour ozone NAAQS through 2012, and to meet the requirements of
the EAC Protocol.
(a) Gasoline Reid Vapor Pressure (RVP). Chapter II A. of the Denver
EAC plan describes the RVP control measure. Since 1991, gasoline sold
in the Denver area during the summer ozone season (for gasoline RVP,
this is defined as June 1 through September 15) has been subject to an
EPA national rule that requires an RVP of 7.8 psi (see 55 FR 23658,
June 11, 1990, and 56 FR 64704, December 12, 1991.) This RVP
requirement of 7.8 psi was applicable to the Denver 1-hour ozone NAAQS
nonattainment area as defined in the Federal Register (see 56 FR 56694,
November 6, 1991.) From 1992 through the 2003 summer ozone season, and
in response to waiver petitions from the Governor of Colorado, we
either waived or granted enforcement discretion for the 7.8 psi RVP
requirement for the Denver area and instead allowed the less stringent
9.0 psi RVP. Our decisions were based on evidence that demonstrated the
7.8 psi RVP was not necessary given the Denver area's record of
continued attainment of the 1-hour NAAQS using the 9.0 psi RVP
requirement and additional evidence presented by the State that showed
economic hardship to consumers and industry if the 7.8 psi RVP level
was imposed.
Since 1999, and in response to a request from the RAQC, refiners
serving the Denver area voluntarily provided gasoline with an RVP of
8.5 psi or lower to help reduce evaporative emissions of VOCs from
refueling and vehicle operations. Through the Denver EAC stakeholder
meetings, the RAQC, State, and industry elected to commit to a gasoline
RVP of 8.1 psi to help reduce VOC emissions. Therefore, the Denver EAC
plan and 2007 dispersion modeled attainment demonstration took credit
for the more stringent RVP level of 8.1 psi. On January 12, 2004, the
Colorado Petroleum Association (CPA) submitted a request to EPA for
enforcement discretion for the 7.8 psi RVP requirement for June 1, 2004
through September 15, 2004. In their January 12, 2004 letter, CPA
acknowledged their continuing efforts with CDPHE and the RAQC in
developing the Denver EAC plan using an RVP of 8.1 psi, but asked that
EPA grant enforcement discretion for a 9.0 psi RVP with CPA's offer to
meet the prior voluntary 8.5 psi RVP level. However, quality-assured
ozone monitoring data for 2001, 2002, and 2003 showed that three of the
ozone ambient air quality monitors in the Denver area's network
recorded violations of the 8-hour ozone NAAQS. In a letter dated March
25, 2004, we explained that primarily based on the monitored violations
of the 8-hour ozone NAAQS and public health issues, enforcement
discretion was not warranted and that the Federal requirement for 7.8
psi RVP gasoline for the Denver area would be effective beginning June
1, 2004. We note that, although the Denver EAC plan and attainment
demonstration dispersion modeling take credit for 8.1 psi RVP
conventional gasoline (9.1 psi RVP for ethanol blends), the Denver area
will instead be realizing greater evaporative VOC emissions reductions
due to EPA's requirement for 7.8 psi RVP. \5\
---------------------------------------------------------------------------
\5\ The requirement for conventional gasoline is an RVP of 7.8
psi. However, the CAA allows an additional 1.0 psi increase for
gasoline blended with ethanol. In the Denver EAC attainment
demonstration dispersion modeling, the State assumes a 25 percent
market penetration for ethanol blended gasoline.
---------------------------------------------------------------------------
An additional RVP issue is found in the third paragraph in Chapter
II A. of the Denver EAC plan which states:
Therefore, since this EAC ozone action plan for the 8-hour ozone
standard relies on an RVP level of 8.1 psi (9.1 psi for ethanol
blends) in the 2007 control case inventory for the existing Denver
1-hour ozone attainment/maintenance area, the State of Colorado
requests a three year waiver establishing an 8.1 psi (9.1 psi for
ethanol blends) RVP level for the existing Denver 1-hour attainment/
maintenance area through the 2007 summer ozone season.
We view this and related language in the SIP as a petition to EPA
to establish an 8.1 psi RVP standard for the Denver area rather than
the currently applicable 7.8 psi RVP standard. A revision to the
federal RVP standard can only be done via rulemaking under section 211
of the CAA, and the authority to conduct such rulemaking cannot be
delegated from the Administrator of EPA to the Regional Administrator
of EPA Region VIII. Hence, Colorado's RVP petition cannot be addressed
in this SIP rulemaking. Our inability to act on Colorado's RVP petition
does not affect our ability to propose approval of the EAC plan because
the currently applicable standard--7.8 psi RVP--will reduce VOC
emissions more than the 8.1 psi RVP standard the State relied on to
model attainment in 2007.
(b) Oil and Gas Exploration and Production (E&P) Condensate Tank
Controls. The Denver EAC plan and attainment demonstration include a
reduction in flash emissions of VOCs from new control equipment to be
installed on E&P condensate collection, storage, processing and
handling operations. Revisions to Colorado's Regulation No. 7 (also
being proposed for approval with this action and described in section
VIII below) require the installation of air pollution control
technology to achieve at least a 47.5 percent reduction in VOC
emissions from E&P production operations, natural gas compressor
stations, and natural gas drip stations located in the Denver EAC plan
area.
(c) Controls for Stationary Reciprocating Internal Combustion
Engines (RICE). The Denver EAC plan and attainment demonstration
include VOC and NOX emission reductions from new control
equipment to be installed on new and existing rich burn and lean burn
natural gas-fired RICE engines larger than 500 horsepower. Chapter II
C. states that emission control equipment for uncontrolled rich burn
RICE shall be non-selective catalyst reduction and an air fuel ratio
controller or other equally effective air pollution control technology.
Chapter II C. also states that for uncontrolled lean burn RICE,
emission control equipment shall be oxidation catalyst reduction or
other equally effective air pollution control technology. These RICE
controls are contained in revisions to Colorado's Regulation No. 7.
[[Page 28246]]
(d) Controls for Dehydration Units. Chapter II D. of the Denver EAC
plan and the attainment demonstration include VOC emission reductions
from new control equipment to be installed on new and existing
dehydration towers, with VOC emissions in excess of 15 tons per year,
located at oil and gas operations. These new control requirements are
contained in revisions to Colorado's Regulation No. 7.
(e) Revisions to Colorado's Regulation No. 11--Automobile
Inspection and Readjustment Program. Chapter II E. of the Denver EAC
plan and the attainment demonstration include VOC and NOX
emission reductions from revisions to Regulation No. 11. These
revisions reduce the coverage of the remote sensing clean screen area
in order to reduce the disbenefit of the clean screen program and to
reflect the practical reality of potential coverage. No more than 50%
of the fleet of gasoline vehicles in the enhanced I/M program area
(described in Regulation No. 11) of applicability will be evaluated
with remote sensing during any twelve-month period after December 31,
2005. These revisions to Colorado's Regulation No. 11 are also being
proposed for approval with this action. For further discussion, see
section IX below.
3. Maintenance for Growth--Continuing Planning Process
The State's methodology and demonstration of maintenance of the 8-
hour ozone NAAQS is described in Chapter III H. of the Denver EAC plan
and our evaluation is described further in section VII C. below. We
note, however, that an oversight occurred in which the State failed to
include a discussion in the Denver EAC plan as to how it would address
the Protocol's continuing planning process provisions. To address this
issue, the State submitted a commitment letter, dated March 22, 2005,
that detailed the specific measures it would use to address the
continuing planning requirements of the Protocol.
The State will periodically evaluate the data and growth
assumptions used in the attainment demonstration, review point source
growth, and review transportation patterns. If these periodic reviews
demonstrate a need to adopt additional control measures, the State will
evaluate and adopt the necessary controls for the Denver EAC plan. The
State also noted that the transportation patterns and emissions in the
Denver EAC plan's 8-hour ozone control area are already evaluated due
to the transportation conformity requirements of currently approved
maintenance plans (i.e., Denver PM10, Denver carbon monoxide, Denver 1-
hour ozone, Fort Collins carbon monoxide, Greeley carbon monoxide, and
Longmont carbon monoxide). The State's letter also contained a
commitment to amend the Denver EAC plan, as a SIP revision, to
incorporate the continuing planning process language from our Protocol.
This SIP revision will be performed in 2005. However, due to State-
internal SIP processing requirements, it will not be submitted to EPA
until 2006.
In addition to the above, we note that once the Denver area
receives an effective attainment designation in 2008, the area will
then have to meet the requirements of 40 CFR 51.905(a)(4) and 40 CFR
51.905(a)(4)(ii). To meet the requirements of 40 CFR 51.905(a)(4)(ii),
the State will have to submit a CAA section 110(a)(1) maintenance plan
within three years of the designation of attainment (i.e., 2011). In
the State's March 22, 2005 letter, it acknowledges this obligation and
also states its intention to prepare this required maintenance plan in
an earlier time period.
Based on the contents of the March 22, 2005 commitment letter, we
have determined that the State has adequately addressed the continuing
planning process requirements of the Protocol.
VII. EPA's Evaluation of the Denver Early Action Compact Ozone Plan's
Attainment Demonstration
Chapter III of the Denver EAC plan contains descriptions and
results of the attainment demonstration photochemical dispersion
modeling, including relative reduction factors (RRF), 2007 design
values, 2007 control case inventories, a 2007 control case
demonstration, and weight of evidence analyses.
A. Photochemical Dispersion Modeling
1. Model Approach Selected. The State selected the EPA-approved
photochemical model ``Comprehensive Air Quality Model with Extensions''
(CAMx). The State's contractors, ENVIRON International Corporation and
Alpine Geophysics Atmospheric Sciences Group performed the modeling
work. Meteorological fields for input into the CAMx model were produced
with the Mesoscale Meteorological Model (MM5). Emissions data,
previously described above, were processed with the Emissions
Processing System (EPS2x) for 2002 and 2007. The photochemical
dispersion modeling was performed in accordance with our then available
draft May 1999 modeling guidance entitled ``Draft Guidance on the Use
of Models and Other Analyses in Attainment Demonstrations for the 8-
hour Ozone NAAQS.'' A more in-depth discussion of the modeling protocol
is located in appendix A (``Modeling Protocol, Episode Selection, and
Domain Definition'') of the State's TSD which is included with the
docket for this action.
2. Modeling Domain. The Denver EAC plan's air quality modeling
domains were defined on an MM5 system with 36 kilometer (km), 12 km,
and a 4 km nested-grid structure. This structure was utilized in
conjunction with the CAMx and EPS2x air quality and emissions modeling
during the episode periods that are described below. The larger 36km
domain was selected to address the impact of boundary condition
uncertainties for the Front Range area of Colorado, as CDPHE was
concerned there may be transport from Southern California and Texas.
The 12 km grid resolution domain essentially covers the central Rocky
Mountain states or portions thereof (i.e., Arizona, Colorado, New
Mexico, Utah and Wyoming.) The 4 km nested-grid was used for the period
encompassing the final, selected ozone episode of June 25, 2002 to July
1, 2002 to provide finer resolution of the emissions, transport, and
transformation, and to evaluate the selected control strategies for the
Denver EAC area and nearby Front Range cities. A more in-depth
discussion of the modeling domain is located in Appendix A (``Modeling
Protocol, Episode Selection and Domain Definition'') of the State's
TSD.
3. Episode Selection. Initially, the State, RAQC, and the modeling
contractors evaluated three 2002 ozone episodes. These episodes were
June 8 to June 12, June 25 to July 1, and July 18 to July 21. The June
8 to June 12 episode was removed from consideration due to the problems
associated with the Hayman wildfire that started on June 8, 2002. The
potential influx of emissions along with the effects of the large smoke
plume made this episode unsuitable for use. Both the June 25 to July 1
and July 18 to July 21 episodes were modeled. However, the results for
the July 18 to July 21 episode were unable to conform to the necessary
model performance standards required by our 8-hour ozone NAAQS modeling
guidance (``Draft Guidance on the Use of Models and Other Analyses in
Attainment Demonstrations for the 8-hour Ozone NAAQS.'') It appears
that the poor model performance for this episode was due to convective
meteorological conditions that could not be resolved by MM5. However,
the results for the June 25 to July 1 episode were successful in
[[Page 28247]]
meeting our modeling guidance and were used for the Denver EAC ozone
plan's attainment demonstration. Additional discussion on episode
selection can be found in section D of our TSD and in Appendix B of the
State's TSD.
4. Base Case Relative Reduction Factors (RRF). The dispersion
modeling for the Denver EAC plan produced base case relative reduction
factors (RRF) for receptors in the modeling domain where ozone monitors
are located. In general, the RRF for each monitor is equal to the mean
2007 base case modeled 8-hour ozone concentration divided by the mean
2002 base case modeled 8-hour ozone concentration. Once the RRFs are
developed, the RRF for each monitoring site is multiplied by the
monitoring site's base case design value to determine a future case
design value (i.e., 2007) to indicate if attainment is demonstrated at
each site. This is further discussed in Chapter III B. and C. of the
Denver EAC plan. Twelve Front Range ozone monitors were considered by
the State, ranging from Fort Collins to the north of metropolitan
Denver, in Larimer County, to the Chatfield reservoir in the
southwestern portion of metropolitan Denver, and also including an
ozone monitor operated by the National Park Service (NPS) just outside
the eastern border of Rocky Mountain National Park in Larimer County.
The current (2001-2003) base case ozone design values used in the
Denver EAC plan and attainment demonstration are based on monitoring
data from 2001, 2002, and 2003. In these three years of data, three of
the twelve monitors were violating the 8-hour ozone NAAQS. They are:
(1) The Chatfield (hereafter Chatfield) reservoir monitor, located in
Douglas County, Air Quality System (AQS) site identification number
080350002, (2) the National Renewable Energies Laboratory (hereafter
NREL) monitor, located in Jefferson County, AQS identification number
080590011, and (3) the Rocky Flats North (hereafter Rocky Flats)
monitor, located in Jefferson County, AQS identification number
080590006. For the violating monitors, we have extracted RRF
information from Table 6 of the Denver EAC plan and present it below in
our Table VII-1:
Table VII-1.--RRF for Violating Monitors
------------------------------------------------------------------------
8-hour
ozone 8-hour
current Base case ozone
(2001-2003) relative future
Monitoring site name base case reduction (2007) base
design factors case design
values in (RRF) values in
ppm ppm
------------------------------------------------------------------------
Chatfield........................ 0.085 0.9807 0.0834
NREL............................. 0.085 0.9946 0.0845
Rocky Flats...................... 0.087 0.9942 0.0865
------------------------------------------------------------------------
Table VII-1 represents the 2007 base case modeling which relied on
expected emission reductions from existing State controls, existing
Federal rules, and anticipated reductions from new Federal rules. As is
clear from Table VII-1 above and the Denver EAC plan, additional
emission reductions are necessary to bring the Rocky Flats monitor
towards modeled attainment for 2007. The 2007 ``control case'' emission
inventories and modeling are described below and in Chapter III. E and
F of the Denver EAC plan. Further discussions are found in sections C
and D of our TSD and in Appendices F, J, K, and L of the State's TSD.
5. 2007 Control Case Emission Inventories. The 2007 control case
emission inventories reflect estimated VOC and NOX emission
reductions from the control strategies described in Chapter III. E of
the Denver EAC plan and in section VI B.2. above. In addition to
emission reductions from existing State and Federal rules, for 2007 the
State calculated the following:
(a) 10 tons per day (tpd) VOC reductions from an 8.1 psi RVP for
conventional gasoline with 9.1 psi RVP for ethanol blends (9 tpd from
on-road vehicles, 1 tpd from refueling, and assuming 25% market
penetration for ethanol blends),
(b) 55 tpd VOC reductions from control of oilfield flash emissions,
(c) 5.5 tpd VOC reductions and 19 tpd NOX reductions
from oilfield RICE controls, and,
(d) 0.5 tpd VOC reductions from the control of oilfield
dehydrators.
The State calculated total emission reductions from existing and
new State and Federal rules for the 2007 control case of 106 tpd of VOC
emissions and 58 tpd of NOX emissions for the eight-county
metropolitan Denver area (counties of Adams, Arapahoe, Boulder,
Broomfield, Denver, Douglas, Jefferson, and Weld) and slightly greater
tons per day for the eleven-county area (adding Elbert, Larimer, and
Morgan counties to the other eight). These projected emission
reductions were extracted from Chapter III. E of the Denver EAC plan
(Tables 7a, 7b, 8a, and 8b) and are presented below in our Tables VII-2
and VII-3:
Table VII-2.--Summary of Emissions Tons Per Average Episode Day (TPD)
Emissions for Adams, Arapahoe, Boulder, Broomfield, Denver, Douglas,
Jefferson, and Weld Counties
------------------------------------------------------------------------
2007 VOCs 2007 NOX
Source category 2007 VOCs 2007 NOX control control
base case base case case case
------------------------------------------------------------------------
Point Sources............... 204.1 107.1 143.3 88.3
Area Sources................ 104.1 27.6 104.1 27.6
Non-Road Sources............ 53.7 82.5 53.5 82.6
On-Road Sources............. 117.5 119.3 108.4 119.0
Subtotal Anthropogenic...... 479.4 336.5 409.3 317.5
Biogenics................... 468.1 37.1 468.1 37.1
------------
[[Page 28248]]
Total................... 947.5 373.6 877.4 354.6
------------------------------------------------------------------------
Table VII-3.--Summary of Emissions Tons Per Average Episode Day (TPD) Emissions for Adams, Arapahoe, Boulder,
Broomfield, Denver, Douglas, Elbert, Jefferson, Larimer, Morgan, and Weld Counties
----------------------------------------------------------------------------------------------------------------
2007 VOCs 2007 NOX
Source category 2007 VOCs 2007 NOX control control
base case base case case case
----------------------------------------------------------------------------------------------------------------
Point Sources............................................... 209.3 144.9 148.1 126.1
Area Sources................................................ 119.6 32.7 119.6 32.7
Non-Road Sources............................................ 62.6 92.4 62.6 93.3
On-Road Sources............................................. 135.1 136.6 126.0 136.3
Subtotal Anthropogenic...................................... 526.6 406.6 456.4 388.4
Biogenics................................................... 799.5 52.3 799.5 52.3
--------------
Total................................................... 1326.1 458.9 1255.8 440.7
----------------------------------------------------------------------------------------------------------------
6. 2007 Control Case Modeling Demonstration. The State modeled the
above base case and control case scenarios with CAMx. As discussed
above and in Chapter III. F of the Denver EAC plan, the 2007 base case
and 2007 control case modeling produce relative reduction factors (RRF)
for receptors in the modeling domain where ozone ambient air quality
monitors are located. Table VII-4 below presents the 2007 control case
RRFs, 2007 control case design values for modeled days greater than
0.070 ppm, and control case design values for modeled days greater than
0.080 ppm for the Chatfield, NREL, and Rocky Flats monitors. We note
that the nine other monitors listed in Table 9 of the Denver EAC plan
all show predicted attainment with values less than 0.081 ppm for both
evaluation days (i.e., modeled days greater than 0.070 ppm and greater
than 0.080 ppm.)
Table VII-4
----------------------------------------------------------------------------------------------------------------
Days > Days > Days > Days >
8-hour 0.070 (ppm) 0.070 (ppm) 0.080 (ppm) 0.080 (ppm)
ozone base ---------------------------------------------------
case design 2007 2007
Monitoring site name values 2001- 2007 control 2007 control
2003 (ppm) control case design control case design
case RRF values case RRF values
(ppm) (ppm)
----------------------------------------------------------------------------------------------------------------
Chatfield...................................... 0.085 0.9761 0.0830 0.9779 0.0831
NREL........................................... 0.085 0.9891 0.0841 0.9748 0.0829
Rocky Flats.................................... 0.087 0.9888 0.0860 0.9811 0.0854
----------------------------------------------------------------------------------------------------------------
In Section D of our TSD and in Appendix I of the State's TSD,
results are presented for the final modeling runs for the June 25, 2002
to July 1, 2002 episode. These results reflect incorporation of all the
control measures for the 2007 attainment year. However, CAMx still
predicts that the Rocky Flats monitor will marginally exceed the 8-hour
ozone NAAQS. The information is presented below in Table VII-5.
Table VII-5
------------------------------------------------------------------------
2001-2003 design 2007 predicted
Monitoring site value design value
------------------------------------------------------------------------
Chatfield........................ 85 ppb............ 82.9 ppb
NREL............................. 85 ppb............ 83.9 ppb
Rocky Flats...................... 87 ppb............ 85.9 ppb
------------------------------------------------------------------------
As can be seen above in Tables VII-4, VII-5, and Table 9 of the
Denver EAC plan, the Rocky Flats monitor was unable to demonstrate
attainment with the 2007 control case emission reduction strategies.
The State and its modeling contractor performed additional sensitivity
analyses, that are described further in section D of our TSD and
Appendix K of the State's TSD. They concluded, based on the anomalous
meteorological conditions in 2003 and the under-prediction tendency of
the CAMx model, for the Denver EAC plan application, that a weight of
evidence (WOE) demonstration was warranted. A WOE demonstration
provides corroborating evidence and technical analysis, beyond the
dispersion modeling, to support a conclusion that attainment is likely
to occur. Weight of evidence demonstrations may be accepted by EPA and
have been approved in prior 1-hour ozone dispersion-modeled
demonstrations of attainment. We also describe their use in our May,
1999 draft guidance for the 8-hour ozone NAAQS (``Draft Guidance on the
Use of Models and Other Analyses in Attainment Demonstrations for the
8-hour Ozone NAAQS.'')
[[Page 28249]]
B. Weight of Evidence Determination
As described in Chapter III. G of the Denver EAC plan and in our
May, 1999 draft modeling guidance for the 8-hour ozone NAAQS, if
resultant values of the dispersion modeling for an attainment
demonstration are between 0.084 ppm and 0.089 ppm at one or more
monitoring site receptor locations, then a WOE determination should be
performed. Since the final modeled design value at the Rocky Flats
monitoring site is predicted to be below 0.089 ppm, our guidance
indicates that corroborating evidence, based on other analyses, can be
sufficiently convincing to support a conclusion that attainment is
likely to occur despite the outcome of the dispersion modeling. To the
State and its contractors, the modeling results appear to be very
``stiff ''; that is, the estimated 2007 design values are not very
sensitive to local emission controls. The State indicated in Chapter
III. G of the Denver EAC plan that they believe this lack of
sensitivity is primarily caused by the following: (1) Anomalous
temperatures and low mixing heights in 2003 were more conducive to
ozone formation than the meteorological conditions that were used in
the 2002 modeling episode, (2) the model's tendency, despite achieving
most of EPA's model performance goals, to under-predict ozone
concentrations and thus under-predict the beneficial impact of local
control measures, and (3) potential influence from elevated, upwind
background concentrations of ozone and ozone precursor emissions that
were detected by the air quality monitors in 2003, but unaccounted for
in the photochemical modeling.
The following describes aspects of the State's WOE analysis:
1. Anomalous Meteorological Conditions in 2003 and Trends Analysis.
The Denver EAC plan's photochemical modeling was designed with ozone
episode days and meteorological data from 2002. However, with the 8-
hour ozone violations detected in 2003, the 2002-based photochemical
modeling was then applied to address these higher 2003 ozone values. It
was discovered, though, that meteorological conditions were
significantly different between 2002 and 2003 and this affected the
photochemical model's performance. One evaluation method the State
applied to address this issue was to provide meteorological data that
indicated that 2003 had record-setting maximum ambient temperatures and
lower than average mixing heights, both of which contributed to the
elevated 2003 monitored 8-hour ozone values. If the extreme high
ambient temperatures and low-level mixing heights of summer 2003 are
excluded, a 1993 to 2002 trends analysis shows a 1.2% annual reduction
in ozone concentrations, which would result in predicted attainment of
the 8-hour ozone NAAQS by 2007. A further discussion is provided in
section D of our TSD and in Appendix N of the State's TSD.
2. Under-Prediction Tendency of the Model. An overall under-
prediction tendency of the model was documented by the State in
Appendixes H and N of their TSD and in section D of our TSD. The model
tended to under-predict 2003 ozone concentrations by approximately 20%.
We note that when a photochemical model underestimates the ozone
concentrations, less ozone is attributed to the local precursor
emissions in the model than resulted from these emissions in reality.
To evaluate this issue, the State's contractor prepared an analysis for
modeled days greater than 70 ppb for the episode days of June 27, 2002
through June 30, 2002. However, for these episode days, only minimal
changes in the predicted ozone values were seen (modeled values were
still low). Only the July 1, 2002 episode day modeling results, with a
model-predicted value of 85 ppb, approached the design value of 87 ppb
and the monitor-observed value of 89 ppb. This is further described in
Chapter III. G, Table 10, of the Denver EAC plan, section D of our TSD,
and in Appendices B, K, and L of the State's TSD.
3. Number of Fine Grid Cell Hours Greater than 84 ppb. The State
evaluated an indicator of the model's performance--the relative change
from the 2002 base case modeling to the 2007 control case modeling with
respect to the predicted ozone concentrations in the 4 km grid cells.
Specifically, the State's contractor found that the number of 8-hour
periods that the model predicted to be greater than 84 ppb for the 2007
control case (4) were 88% fewer than the model predicted for the 2002
base case (33). This 88% figure is greater than the ``large'' reduction
(80%) that is suggested in our 1999 draft 8-hour ozone modeling
guidance and supports the conclusion that the proposed control strategy
package for 2007 is consistent with meeting the 8-hour NAAQS. This
evaluation is further described in section D of our TSD and in Appendix
L of the State's TSD.
4. Relative Difference (RD). Relative Difference (RD) is another
metric the State's contractor evaluated. RD examines the amount by
which the 8-hour ozone concentration is above 84 ppb in the 2007
control case modeling versus the 2002 base case modeling. The State's
contractor computed the ratio of the average estimated ``excess 8-hour
ozone'' for the 2007 control case modeling to the average estimated
``excess 8-hour ozone'' for the 2002 base case modeling. In this case,
we are using the phrase ``excess 8-hour ozone'' to mean the amount by
which the average in the particular year exceeds 84 ppb. The State's
contractor calculated an RD of 93%, which means the 2007 value was 93%
less than the 2002 value. EPA considers large RDs to be desirable, with
anything greater than 80% considered large. Thus, this 93% figure
further supports a conclusion that the control strategy package for
2007 is consistent with meeting the 8-hour NAAQS. This evaluation is
further described in section D of our TSD and in Appendix L of the
State's TSD.
5. VOC and NOX Sensitivity. The State and its contractor
performed sensitivity modeling runs looking at reductions in VOCs, VOCs
and NOX, and just NOX. The sensitivity analyses
indicated that VOC reductions alone were more important for achieving
reductions in ozone values in the urbanized area and at the Rocky Flats
air quality monitoring location. This also helped confirm the validity
of the 2007 control strategy package which focused on VOC controls.
This evaluation is further described in section D of our TSD and in
Appendixes J and K of the State's TSD.
In summary, the State's WOE analyses provide adequate support for
the State's attainment demonstration. Our decision on the adequacy of
the WOE is based on the composite of the analyses, and not on any
single element. The WOE complements the modeled 2007 control strategies
and indicates that attainment should be reached by December 31, 2007 as
is required by the EAC Protocol.
C. Maintenance Through 2012
The EAC Protocol requires that, in addition to demonstrating
attainment of the 8-hour ozone NAAQS in 2007, areas demonstrate
maintenance of the 8-hour ozone NAAQS through 2012. For the Denver EAC
plan, the State performed a comparison of projected emissions, from all
source categories, for 2012 to those used in the 2007 dispersion
modeled attainment demonstration (as supported by WOE.) The 2012
emission inventories assume that the 2007 control strategies remain in
place through 2012. The 2012 emission inventories also account for
Federal emission control measures that are scheduled to take effect in
the 2007 to 2012 time period. As the 2012 projected emissions are less
than the 2007 dispersion modeled
[[Page 28250]]
emissions in the attainment demonstration, continued maintenance is
demonstrated. The 2007 control case emission inventories for the 8-
county area and the 11-county area, along with the 2012 maintenance
emission inventories, are presented in Chapter III E. Tables 7a, 7b,
8a, and 8b respectively and also in our Tables VII-6 and VII-7 below.
Table VII-6.--Summary of Emissions Tons Per Average Episode Day (TPD) Emissions for Adams, Arapahoe, Boulder,
Broomfield, Denver, Douglas, Jefferson, and Weld Counties
----------------------------------------------------------------------------------------------------------------
2007 VOCs 2012 VOCs 2007 NOX 2012 NOX
Source category control control control control
case case case case
----------------------------------------------------------------------------------------------------------------
Point Sources............................................... 143.3 152.9 88.3 96.5
Area Sources................................................ 104.1 114.0 27.6 31.1
Non-Road Sources............................................ 53.5 47.7 82.6 74.8
On-Road Sources............................................. 108.4 76.0 119.0 77.7
Subtotal Anthropogenic...................................... 409.3 390.6 317.5 280.1
Biogenics................................................... 468.1 468.1 37.1 37.1
--------------
Total................................................... 877.4 858.7 354.6 317.2
----------------------------------------------------------------------------------------------------------------
Table VII-7.--Summary of Emissions Tons Per Average Episode Day (TPD) Emissions for Adams, Arapahoe, Boulder,
Broomfield, Denver, Douglas, Elbert, Jefferson, Larimer, Morgan, and Weld Counties
----------------------------------------------------------------------------------------------------------------
2007 VOCs 2012 VOCs 2007 NOX 2012 NOX
Source category control control control control
case case case case
----------------------------------------------------------------------------------------------------------------
Point Sources............................................... 148.1 159.2 126.1 138.1
Area Sources................................................ 119.6 131.3 32.7 36.7
Non-Road Sources............................................ 62.6 56.2 93.3 84.6
On-Road Sources............................................. 126.0 89.0 136.3 90.1
Subtotal Anthropogenic...................................... 456.4 435.7 388.4 349.4
Biogenics................................................... 799.5 799.5 52.3 52.3
--------------
Total................................................... 1255.8 1235.2 440.7 401.8
----------------------------------------------------------------------------------------------------------------
Our review of the attainment demonstration shows that it should be
approved. The State has adopted acceptable control strategies and has
performed modeling that meets our modeling guidance requirements for
the 8-hour ozone NAAQS and the EAC Protocol. Modeling based on newly
adopted and existing control measures, and supplemented by a weight-of-
evidence analysis, demonstrates attainment by December 31, 2007 and
maintenance through 2012. Therefore, we are proposing to approve the
attainment demonstration.
VIII. EPA's Evaluation of the Regulation No. 7 Revisions
Colorado's Regulation No. 7 is entitled ``Emissions of Volatile
Organic Compounds'' (hereafter, Regulation No. 7). In conjunction with
the development of the Denver EAC plan, the State made several changes
and/or additions to sections I.A., I.B., XII, and XVI of Regulation No.
7 which the AQCC adopted after its March 12, 2004, public hearing.
These Regulation No. 7 revisions were submitted to us by the Governor
on July 21, 2004. Based on input and discussions with EPA, the AQCC
further amended Regulation No. 7 on December 16, 2004, following a
public hearing. The Governor submitted these additional revisions to
Regulation No. 7 to us on March 24, 2005. These March 24, 2005
Regulation No. 7 revisions supersede and replace those submitted by the
Governor on July 21, 2004, and are those we are proposing to approve.
The purpose of the revisions to Regulation No. 7 was to reduce
emissions of: (1) VOCs from condensate tanks and operations at oil and
gas exploration and production (E&P) facilities, (2) VOCs and
NOX from stationary and portable oilfield reciprocating
internal combustion engines (RICE), (3) VOCs from gas processing
plants, and (4) VOCs from dehydrators at oilfield operations. These
revisions to Regulation No. 7 apply to all affected facilities within
the 8-hour ozone nonattainment area boundary, with the majority of
affected facilities being located in southern Weld County.
The revisions to Regulation No. 7 affect the following sections:
A. Sections I.A. and I.B. Including definitions of the Denver 1-
hour ozone area and the Denver 8-hour ozone control area. Also
indicating that new and existing oil and gas operations come under the
provisions of sections XII and XVI..
B. Section II.A., additional definitions.
C. A new Section XII, ``Volatile Organic Compound Emissions From
Oil And Gas Operations.'' Includes definitions, percentages of emission
reductions for the high ozone season and rest of the year, numerous
recordkeeping requirements for a spreadsheet to determine daily
compliance, emission factors used to demonstrate compliance, reporting
requirements for certain equipment if a construction or Title V permit
is issued by the State, methodology for approval of alternative
emissions control equipment, requirements for gas-processing plants,
requirements for controlling emissions from dehydration units, and a
methodology for approval to develop testing methods and revised
emission factors.
D. A new Section XVI, ``Control of Emissions From Stationary And
Portable Engines in the 8-hour Ozone Control Area.'' Includes specific
requirements for emission control technology for applicable RICE and
dates for the removal or replacement with electric units for certain
existing internal combustion engines.
One of the major requirements of the changes is an overall
reduction of 47.5% of VOCs from E&P condensate storage tanks during the
summer ozone season to meet the modeled requirements of the
[[Page 28251]]
attainment demonstration. Due to the unique operating parameters and
numerous tanks in the field (in excess of 1,000), the AQCC allowed an
overall averaging approach, rather than a unit-by-unit approach, to
achieve the necessary emission reductions. The regulation includes
detailed record keeping requirements to help ensure the 47.5% reduction
requirement is met.
We have reviewed, and are proposing approval of, all of the above
State-adopted revisions to Regulation No. 7.
IX. EPA's evaluation of the Regulation No. 11 Revisions
Colorado's Regulation No. 11 is entitled ``Motor Vehicle Emissions
Inspection Program'' (hereafter referred to as Regulation No. 11). This
program has undergone several revisions since 2000, including revisions
that were adopted by the AQCC in conjunction with the Denver EAC plan
after the March 11-12, 2004 public hearing. The prior Regulation No. 11
revisions that the Governor submitted on June 20, 2003 and April 12,
2004 are briefly described below. The revisions the Governor submitted
on July 21, 2004 in support of the Denver EAC plan are also described
below:
A. Revisions adopted November 16, 2000, submitted June 20, 2003.
This submittal amended Regulation No. 11 by (1) extending the time
for taking valid remote-sensing readings for purposes of the clean
screen program, and (2) correcting a citation error in a section of the
rule concerning the licensing of clean screen inspectors.
B. Revisions adopted December 20, 2001, submitted June 20, 2003.
This submittal amended Regulation No. 11 by (1) expanding the clean
screen program, (2) excluding El Paso County from the clean screen
program, and (3) repealing the ``Verification of Emissions Test''
certificate or windshield sticker.
C. Revisions adopted August 15, 2002, submitted June 20, 2003.
This submittal amended Regulation No. 11 to switch to a pay-upon-
registration system for the clean screen program. The rule amendments
also included a change to the timing requirements for remote sensing
readings to make the clean screen program more flexible. As amended,
the regulation requires two valid remote sensing readings within a
twelve-month period in order to clean screen a vehicle. The regulation
previously required the most recent reading to be within 120 days of
the registration renewal date. In addition, this submittal included
several minor, housekeeping changes such as:
1. The elimination of a requirement for agencies to develop the
equivalent of a windshield sticker for clean screened vehicles.
2. The elimination of a provision requiring annual inspections for
government vehicles.
3. The repeal of provisions establishing a method to mail payments
to the contractor.
D. Revisions adopted October 17, 2002, submitted June 20, 2003.
This submittal to Regulation No. 11 expanded the pay-upon-
registration for the clean screen program (see the August 15, 2002
version) to the enhanced I/M program area (see the December 20, 2001
version). These revisions also contained provisions that the
malfunction indicator light (MIL) and on-board diagnostic (OBD II)
fault codes will not be used as the basis for test failures and it
eliminated a pre-existing state requirement for vehicles to pass MIL
tests. We note that Federal law does not require MIL or OBD tests for
pre-1996 vehicles.
These revisions also eliminated the requirement for 1996 and newer
vehicles to pass MIL and OBD tests. This particular revision is
acceptable to EPA in view of our final Motor Vehicle Inspection/
Maintenance requirements (see 66 FR 18155, April 5, 2001) which
extended the deadline for beginning OBD inspections to January 1, 2002.
As the Denver metropolitan area was redesignated to attainment for
carbon monoxide on December 14, 2001 (see 66 FR 64751), this January 1,
2002 OBD implementation date was not applicable to the Denver
metropolitan area and the State need not retain the MIL and OBD program
in the SIP.
E. Revisions adopted September 18, 2003, submitted April 12, 2004.
This submittal to Regulation No. 11 allows the sale and
registration of used motor vehicles without an emissions inspection if
the motor vehicle is less than 3 years old. In addition, Regulation No.
11 previously required motor vehicle dealers to have an emissions test
for used vehicles at the time of sale, regardless of when they may have
been inspected before. The rule has been revised such that motor
vehicle dealers need to only have vehicles that are consigned for sale
inspected annually; further inspection is not required at the time of
sale.
F. Revisions adopted December 18, 2003, submitted April 12, 2004.
This submittal to Regulation No. 11 removed the calendar year 2004
and 2005 cutpoints, while retaining the 2006 cutpoints, and also
removed El Paso County (Colorado Springs area) from the Federal
applicability of a basic I/M program.
G. Revisions adopted March 12, 2004, submitted July 21, 2004.
This submittal to Regulation No. 11 supports the Denver EAC plan by
reducing the percentage of the fleet to be clean-screened from a
maximum of 80% to a maximum of 50% after December 31, 2005.
We have reviewed, and are proposing approval of, all of the above
State-adopted revisions to Regulation No. 11.
X. EPA's evaluation of the Common Provisions Regulation Revision
The State amended the Common Provisions Regulation to incorporate
the American Petroleum Institute's (API) definition of ``condensate,''
which refers to hydrocarbon liquids that have an API gravity of 40
degrees or greater.
We have reviewed, and are proposing approval of, this revision to
the Common Provisions Regulation.
XI. Consideration of Section 110(l) of the CAA
Section 110(l) of the CAA 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 a NAAQS or any other applicable requirement of
the CAA. The Denver EAC ozone plan will not interfere with attainment,
reasonable further progress, or any other applicable requirement of the
CAA.
XII. Proposed Action
EPA is proposing to approve the Denver Early Action Compact (EAC)
ozone plan that the Governor submitted on July 21, 2004, the attainment
demonstration, the revisions to Regulation No. 7 that the Governor
submitted on March 24, 2005, all of the revisions to Regulation No. 11,
and the revisions to the Common Provisions Regulation, all as a
revision to the SIP.
Submit your comments, identified by RME Docket Number R08-OAR-2004-
CO-0001, by one of the methods identified above at the front of this
proposed rule. We will consider your comments in deciding our final
action if they are received before June 16, 2005. EPA will address all
public comments in a subsequent final rule based on this proposed rule.
EPA will not institute a second comment period on this action. Any
parties interested in commenting must do so at this time.
[[Page 28252]]
XIII. Statutory and Executive Order Reviews
Under Executive Order 12866 (58 FR 51735, October 4, 1993), this
proposed action is not a ``significant regulatory action'' and
therefore is not subject to review by the Office of Management and
Budget. For this reason, this action is also not subject to Executive
Order 13211, ``Actions Concerning Regulations That Significantly Affect
Energy Supply, Distribution, or Use'' (66 FR 28355, May 22, 2001). This
proposed action merely proposes to approve state law as meeting Federal
requirements and imposes no additional requirements beyond those
imposed by state law. Accordingly, the Administrator certifies that
this proposed rule will not have a significant economic impact on a
substantial number of small entities under the Regulatory Flexibility
Act (5 U.S.C. 601 et seq.). Because this rule proposes to approve pre-
existing requirements under state law and does not impose any
additional enforceable duty beyond that required by state law, it does
not contain any unfunded mandate or significantly or uniquely affect
small governments, as described in the Unfunded Mandates Reform Act of
1995 (Public Law 104-4).
This proposed rule also does not have tribal implications because
it will not have a substantial direct effect 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, as specified by Executive
Order 13175 (65 FR 67249, November 9, 2000). This action also does not
have Federalism implications because it does not have substantial
direct effects on the States, on the relationship between the national
government and the States, or on the distribution of power and
responsibilities among the various levels of government, as specified
in Executive Order 13132 (64 FR 43255, August 10, 1999). This action
merely proposes to approve a state rule implementing a Federal
standard, and does not alter the relationship or the distribution of
power and responsibilities established in the Clean Air Act. This
proposed rule also is not subject to Executive Order 13045 ``Protection
of Children from Environmental Health Risks and Safety Risks'' (62 FR
19885, April 23, 1997), because it is not economically significant.
In reviewing SIP submissions, EPA's role is to approve state
choices, provided that they meet the criteria of the Clean Air Act. In
this context, in the absence of a prior existing requirement for the
State to use voluntary consensus standards (VCS), EPA has no authority
to disapprove a SIP submission for failure to use VCS. It would thus be
inconsistent with applicable law for EPA, when it reviews a SIP
submission, to use VCS in place of a SIP submission that otherwise
satisfies the provisions of the Clean Air Act. Thus, the requirements
of section 12(d) of the National Technology Transfer and Advancement
Act of 1995 (15 U.S.C. 272 note) do not apply. This proposed rule does
not impose an information collection burden under the provisions of the
Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.).
List of Subjects in 40 CFR Part 52
Environmental protection, Air pollution control, Intergovernmental
relations, Nitrogen dioxide, Ozone, Reporting and recordkeeping
requirements, Volatile organic compounds.
Dated: May 6, 2005.
Kerrigan G. Clough,
Acting Regional Administrator, Region VIII.
[FR Doc. 05-9724 Filed 5-16-05; 8:45 am]
BILLING CODE 6560-50-P