[Federal Register Volume 61, Number 132 (Tuesday, July 9, 1996)]
[Proposed Rules]
[Pages 36004-36012]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-17319]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Parts 52 and 81
[CO43-2-6865; CO43-1-6931; FRL-5532-07]
Clean Air Act Approval and Promulgation of State Implementation
Plan for Colorado; Carbon Monoxide Attainment Demonstrations and
Related SIP Elements for Denver and Longmont; Clean Air Act
Reclassification
AGENCY: Environmental Protection Agency (EPA).
ACTION: Notice of Proposed Rulemaking.
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SUMMARY: The Environmental Protection Agency today proposes approval of
the State Implementation Plan (SIP) revisions submitted by the State of
Colorado for the purpose of bringing about the attainment of the
national ambient air quality standards (NAAQS) for carbon monoxide
(CO). The implementation plan revisions were submitted by the State to
satisfy certain Federal requirements for an approvable nonattainment
area CO SIP for Denver and Longmont. This action includes proposed
approval of revisions to Colorado Regulations 11 (vehicle inspection
and maintenance) and 13 (oxygenated fuels) submitted to satisfy
conditions in the SIP. It also includes proposed reclassification of
the Denver CO nonattainment area from Moderate to Serious. The
rationale for the approvals and reclassification are set forth in this
document. Additional information is available at the address indicated
below.
DATES: Comments on this proposed action must be received in writing by
August 8, 1996.
ADDRESSES: Comments should be addressed to: Richard R. Long, Director
of Air Programs (8P2-A), Environmental Protection Agency, Region VIII,
999 18th Street, Suite 500, Denver, Colorado 80202-2466.
Copies of the State's submittals and other information are
available for inspection during normal business hours at the following
locations: Environmental Protection Agency, Region VIII, Air Programs,
999 18th Street, 3rd Floor, South Terrace, Denver, Colorado 80202-2466;
and Colorado Air Pollution Control Division, 4300 Cherry Creek Dr.
South, Denver, Colorado 80222-1530.
FOR FURTHER INFORMATION CONTACT: Jeff Houk at (303) 312-6446.
SUPPLEMENTARY INFORMATION:
I. Background
The air quality planning requirements for moderate CO nonattainment
areas are set out in sections 186-187 of the Clean Air Act (Act)
Amendments of 1990 (CAAA) which pertain to the classification of CO
nonattainment areas and to the submission requirements of the SIP's for
these areas, respectively. The EPA has issued a ``General Preamble''
describing EPA's preliminary views on how EPA intends to review SIP's
and SIP revisions submitted under Title I of the Act, [see generally 57
FR 13498 (April 16, 1992) and 57 FR 18070 (April 28, 1992)]. Because
EPA is describing its interpretations here only in broad terms, the
reader should refer to the General Preamble for a more detailed
discussion of the interpretations of Title I advanced in today's
proposal and the supporting rationale. In today's rulemaking action on
the Denver and Longmont CO SIPs, EPA is proposing to apply its
interpretations taking into consideration the specific factual issues
presented. Thus, EPA will consider any timely submitted comments before
taking final action on today's proposal.
This Federal Register document specifically addresses several
requirements of the 1990 CAAA which were required to be submitted no
later than November 15, 1992, and which the State did not submit by
that date. These requirements include an attainment demonstration,
contingency measures and, for Denver, a vehicle miles travelled
forecasting and tracking program and transportation control measures.
EPA made a formal finding that the State had failed to submit these SIP
revisions in a letter to Governor Roy Romer dated January 15, 1993.
This Federal Register document also addresses revisions to Regulations
11 and 13, submitted by the State of Colorado to implement portions of
the control strategy relied upon by the attainment demonstration.
Section 187(a)(7) required those States containing CO nonattainment
areas with design values greater than 12.7 parts per million (ppm) to
submit, among other things, an attainment demonstration by November 15,
1992, demonstrating that the plan will provide for attainment by
December 31, 1995 for moderate CO nonattainment areas and December 31,
2000 for serious CO nonattainment areas. The attainment demonstration
must include a SIP control strategy, which is also due by November 15,
1992. The SIP control strategy for a given nonattainment area must be
designed to ensure that the area meets the specific annual emissions
reductions necessary for reaching attainment by the deadline. In
addition, section 187(a)(3) requires these areas to implement
contingency measures if any estimate of actual vehicle miles travelled
(VMT) or any updated VMT forecast for the area contained in an annual
report for any year prior to attainment exceeds the number predicted in
the most recent VMT forecast. Contingency measures are also triggered
by failure to attain the NAAQS for CO by the attainment deadline.
Contingency measures must be submitted with the CO SIP by November 15,
1992. Finally, a vehicle miles travelled forecasting and tracking
program is required by Section 187(a)(2)(A), and transportation control
measures are required for Denver by Section 187(a)(2)(B). These
requirements are discussed in more detail below and in the Technical
Support Document for this proposed action.
Longmont had been designated as unclassifiable/attainment prior to
passage of the 1990 CAAA. However, a special monitoring study in 1988-
89 recorded an exceedance of the NAAQS in Longmont. As a result, EPA
Region VIII recommended that the Governor designate this area
nonattainment, and on March 15, 1991, the Governor submitted a
nonattainment designation for this area that was later codified by EPA
at 40 CFR Part 81. Since this area had never had a SIP, EPA interpreted
Section 172 of the Act to require an attainment demonstration for
Longmont. Contingency measures under Section 172(c)(9) were also
required. On January 15, 1993, EPA made a formal finding that the State
had failed to submit these SIP revisions for Longmont.
On July 11, 1994 and July 13, 1994, Governor Roy Romer submitted
comprehensive revisions to the Colorado SIP. The carbon monoxide SIP
element submittals for Denver and Longmont addressed the outstanding
CAA requirements discussed above, as well as other CAA mandates. The
July 11, 1994 CO SIP revision for Denver was developed primarily by the
Colorado Department of Health's Air Pollution Control Division (APCD),
the Colorado Air Quality Control Commission (AQCC), and the Regional
Air Quality Council (RAQC), which represents local government and
citizen interests. The July 13, 1994 CO SIP revision for Longmont was
developed primarily by the APCD, in consultation with the City of
Longmont.
[[Page 36005]]
The Act requires States to observe certain procedural requirements
in developing implementation plans and plan revisions for submission to
EPA. Section 110(a)(2) of the Act provides that each implementation
plan submitted by a State must be adopted after reasonable notice and
public hearing.1 Section 110(l) of the Act similarly provides that
each revision to an implementation plan submitted by a State under the
Act must be adopted by such State after reasonable notice and public
hearing.
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\1\ Also, Section 172(c)(7) of the Act requires that plan
provisions for nonattainment areas meet the applicable provisions of
section 110(a)(2).
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The EPA also must determine whether a submittal is complete and
therefore warrants further EPA review and action [see section 110(k)(1)
and 57 FR 13565]. The EPA's completeness criteria for SIP submittals
are set out at 40 CFR Part 51, Appendix V (1991), as amended by 57 FR
42216 (August 26, 1991). The EPA attempts to make completeness
determinations within 60 days of receiving a submission. However, a
submittal is deemed complete by operation of law if a completeness
determination is not made by EPA within six months after receipt of the
submission.
The AQCC held a public hearing on June 16, 1994 to entertain public
comment on the implementation plan revisions for Denver and Longmont.
Following the public hearing, the SIP revisions were adopted by the
AQCC, and forwarded to the Colorado Legislative Council for review.
(Under Colorado law, SIP revisions imposing new or revised controls on
mobile sources must be reviewed and accepted by the Colorado
Legislative Council.) The AQCC held an emergency hearing on July 7,
1994, to address concerns with the Denver SIP raised by the Legislative
Council, and on July 11 and July 13, 1994, the SIP revisions were
submitted to EPA by the Governor for approval.
The SIP revision was reviewed by EPA to determine completeness
shortly after its submittal, in accordance with the completeness
criteria set out at 40 CFR Part 51, Appendix V (1991), as amended by 57
FR 42216 (August 26, 1991). The submittal was found to be complete, and
a letter dated July 14, 1994 was forwarded to the Governor indicating
the completeness of the submittal and the next steps to be taken in the
review process. The applicable Clean Air Act requirements and EPA's
rationale for its proposed actions are discussed below.
Denver
A. Attainment Demonstration and Control Strategies
(1) Attainment Demonstration
As noted, CO nonattainment areas with design values greater than
12.7 ppm were required to submit a demonstration by November 15, 1992,
that the plan will provide for attainment by December 31, 1995 for
moderate CO nonattainment areas and December 31, 2000 for serious CO
nonattainment areas. APCD conducted an attainment demonstration using
urban areawide modeling in conjunction with intersection modeling for a
modeling region encompassing the Denver nonattainment area.
The CO NAAQS are for 1-hour and 8-hour periods and are not to be
exceeded more than once per year. The 1-hour CO NAAQS is 35 ppm (40 mg/
m3) and the 8-hour CO NAAQS is 9 ppm (10 mg/m3). The
demonstration predicted that the highest 8-hour design concentration as
of the attainment date will be 8.91 ppm, thus demonstrating attainment
of the 8-hour CO NAAQS. No demonstration was required to be carried out
for the 1-hour NAAQS, as Denver has not violated this NAAQS since
before the 1990 CAAA were enacted. The same strategies which bring the
area into attainment with the 8-hour NAAQS will also contribute to
reduced 1-hour concentrations. The modeled attainment demonstration is
discussed in greater detail below.
(a) Policy Issues: Reclassification to Serious and Applicability of
Serious Area SIP Requirements
(i) Reclassification to Serious. During the SIP development
process, the RAQC conducted an exhaustive review of control strategies
for use in demonstrating attainment of the CO NAAQS by the Clean Air
Act-mandated deadline for moderate areas of December 31, 1995. Even
with the oxygenated fuels program and an enhanced I/M program in place,
the RAQC and APCD determined that a 30% reduction in emissions would
still be needed to attain the NAAQS by this date. Any measures would
need to be implemented in the 18-month period between SIP adoption (in
June 1994) and the attainment date, ruling out many potential
strategies with longer implementation horizons. The RAQC considered
several aggressive strategies, including a mandatory no-drive day for
high emitting vehicles, but was unable to identify a package of
strategies that would provide the necessary emission reductions by
December 31, 1995.
As a result, the RAQC recommended to the AQCC that the Denver area
seek reclassification to serious. If Denver were reclassified to
serious, the applicable attainment date would become December 31, 2000
(CAA Section 186(a)(1)). The AQCC adopted this recommendation, and the
Governor formally requested reclassification to serious in his July 11,
1994 letter submitting the SIP. As part of this Federal Register
document, EPA is proposing to reclassify the Denver-Boulder
nonattainment area to serious.
EPA had originally intended to rely upon the authority for
reclassification provided by Section 110(k)(6) of the Clean Air Act.
This paragraph provides broad authority for EPA to correct previous
approvals, disapprovals, designations, and classifications based on new
information. However, air quality data collected during calendar year
1995 show that the Denver area experienced two exceedances of the CO
NAAQS in 1995 at the CAMP monitor. Because of this, Denver cannot
demonstrate attainment of the NAAQS by the statutory December 31, 1995
attainment date for moderate areas, and must be reclassified, by
operation of law, to serious. Under Section 186(b)(2)(A), a moderate
carbon monoxide nonattainment area must be reclassified as serious by
operation of law if the Administrator finds that the area has failed to
attain the CO NAAQS. Pursuant to Section 186(b)(2)(B), EPA must publish
a document in the Federal Register identifying those areas that failed
to attain the NAAQS and the resulting classifications. In this
document, EPA is proposing to find that the Denver/Boulder carbon
monoxide nonattainment area did not attain the NAAQS by the required
attainment date of December 31, 1995, and to revise the area's
classification for carbon monoxide in 40 CFR Part 81 from moderate to
serious.
(ii) Impacts of Reclassification to Serious. Areas classified as
serious are required to attain the CO NAAQS no later than December 31,
2000. In addition, the following additional requirements of CAA Section
187 apply:
Gasoline sold during the winter months must contain a level of
oxygen necessary to attain the NAAQS. (CAA Section 187(b)(3))
A mandatory employer-based trip reduction program must be adopted
and implemented, unless it can be shown that such a program is not
necessary to demonstrate attainment of the NAAQS. (CAA Section
187(b)(2), referencing CAA Section 182(d)(1)(B))
A December 31, 1995 milestone must be identified, and an economic
[[Page 36006]]
incentive program must be adopted and implemented if the milestone is
not achieved or if the area fails to attain the CO NAAQS by December
31, 2000. (CAA Section 187(d))
Vehicle miles travelled forecasts must be submitted for the period
1996-2000 (submittal of vehicle miles traveled forecasts for 1993-1995
is required for moderate areas). (CAA Section 187(a)(2)(A))
Additional requirements for the content and analysis of
transportation plans, programs and projects apply under the EPA/DOT
transportation conformity regulations (58 FR 62215, November 24, 1993).
The oxygenated gasoline, VMT forecast, and conformity requirements
are discussed elsewhere in this document.
(iii) December 31, 1995 milestone demonstration. CAA Section 187(d)
requires areas classified as serious to submit a demonstration no later
than March 31, 1996, that the area has achieved CO emission reductions
equivalent to the total of the specified annual emission reductions
required by December 31, 1995. The Act does not provide further
guidance on the form or content of the milestone itself, the specified
annual emission reductions, or the nature of the milestone
demonstration. EPA has not issued guidance on this matter.
Since the Act does not prescribe a methodology for determining a
milestone and EPA has not issued guidance for this purpose, the State
has chosen to use its 1995 base case emission inventory as the
milestone (Section XII-D of the SIP). The milestone level is 1396 tons
per day in the nonattainment area; this level represents progress
toward attainment from the 1988 level of 1709 tons per day.
(iv) Employer-based trip reduction program (the ECO program). CAA
Section 187(b)(2) requires areas classified as serious to adopt the
measures required by Section 182(d)(1). These measures consist of
transportation control measures (CAA Section 182(d)(1)(A)) and a
mandatory employer-based travel reduction program (commonly known as
the Employee Commute Options, or ECO, program) (CAA Section
182(d)(1)(B)). Section 187(b)(2) also provides that, in any area
defined as a ``covered area'' under the Clean Fuel Fleet Program
requirements of Section 246(a)(2)(B) (the Denver area meets this
definition), a SIP may exclude any of the Section 182(d)(1) measures if
(1) the SIP includes an explanation of why any measure was not adopted
and what emission reduction measure was adopted to provide comparable
reduction in emissions, or (2) the SIP contains reasons why such
reduction is not necessary to attain the national primary ambient air
quality standard for CO. (As a moderate area, Denver was already
required by the ``Special Rule for Denver,'' Section 187(a)(2)(B), to
address the transportation control measure requirements of Section
182(d)(1)(A). These requirements are discussed in Chapter X of the
SIP.)
The SIP demonstrates that no TCMs are necessary to provide for
attainment of the NAAQS by December 31, 2000 (attainment demonstration,
Tables XII-1 and XII-2). However, several TCMs were adopted as part of
the SIP, including transportation management associations to encourage
and provide technical support for voluntary employer-based trip
reduction activities; financial incentives for subsidized employee
transit passes and other travel reduction strategies for downtown
Denver employees; transit passes for students at the Auraria campus in
downtown Denver; high-occupancy vehicle lanes on Broadway and Lincoln,
two major arterials providing access to the central business district;
and improved traffic signalization in the central business district and
elsewhere in the nonattainment area. Appendix X-A of the SIP also
discusses several other TCMs that were adopted and implemented as part
of the 1979 and 1982 SIPs for Denver and remain in effect.
Section X.F. of the SIP provides the formal justification for
exclusion of the ECO program from the Denver SIP. However, on December
23, 1995, the President signed revisions to the ECO requirements of the
Clean Air Act. These revisions amended the Act to make submittal of a
SIP revision providing for the ECO program voluntary for areas which
are bumped up to a higher classification (and thus, newly made subject
to the requirement). Thus, the State would have no longer been required
to submit such program, even if EPA had initially interpreted the Act
to require this program for Denver.
(b) Technical Evaluation of Attainment Demonstration
EPA is proposing to approve the State's attainment demonstration
for Denver. EPA has determined that the State correctly applied
national guidance in conducting modeling of the entire region and of
six intersections that could potentially cause violations of the CO
NAAQS. In addition, the State complied with a Region VIII request to
conduct modeling of downtown intersections above and beyond the six
required by national guidance. However, due to the factors described
below, the model could not be properly applied to two high-traffic
downtown intersections: Speer/Auraria and Broadway/Colfax. Model
predictions at these two sites were affected by uncertainties in
meteorological and motor vehicle emissions inputs. In addition, the
modeled predictions of high ambient values at these intersections were
not supported by saturation monitoring data obtained at the same
locations. Thus, the attainment demonstration is based on modeled and
monitored values at a third downtown intersection, CAMP, which has
historically recorded the highest CO concentrations in the Denver metro
area. These issues are discussed in greater detail below.
A variety of specialized models were used to model the Denver area
carbon monoxide concentrations in accordance with EPA guidance. The
Urban Airshed Model (UAM) was used to simulate regional concentrations
during two historical episodes when very high carbon monoxide levels
occurred. During these same episodes the CAL3QHC model was used to
simulate concentrations from local streets and roadways. The outputs
from both models were added together so that total predicted
concentrations could be compared with values actually measured at the
monitoring sites during these episodes. These comparisons determine if
the modeling meets the performance criteria prescribed in the UAM
guidance document, and in the modeling protocol. For both episodes
there was a tendency for the UAM/CAL3QHC model to underpredict
concentrations. However, the degree of underprediction was within the
limits specified in EPA UAM Guidance documents, and in the modeling
protocol.
The validated UAM/CAL3QHC model was then applied in the attainment
year (2000) to determine whether proposed control strategies are
sufficient to meet the 8-hour ambient air quality standard (9.0 ppm).
The same meteorological conditions used in the model validation runs
were used in the 2000 model runs. However, the 2000 runs were modeled
with revised emission input files to examine the benefits of the
various control strategies. The 2000 attainment runs showed that the
control strategies in the SIP are sufficient to reduce carbon monoxide
concentrations to less than 9.0 ppm at all locations in the
nonattainment area.
The Denver CO modeling protocol was approved by EPA Region VIII in
[[Page 36007]]
May 1992. Specific intersections to be modeled were not identified in
the protocol. The State showed attainment on each of the six highest
ranked intersections selected for modeling, following screening
criteria contained in ``Guideline for Modeling CO from Roadway
Intersections'', EPA-454/R-92-005. The State subsequently found that
the six busiest intersections for traffic congestion were located in
the suburban areas, where background air quality levels are relatively
low. Application of CAL3QHC at these six locations, combined with UAM
predicted background levels, showed the year 2000 concentrations at
levels well within the CO NAAQS. The Region requested the State to
model an additional intersection in the central business district, to
ensure that control strategies provide for attainment at hot spot
locations in the urban core area, not just at suburban locations
exposed to significantly lower background concentrations.
The State performed preliminary CAL3QHC modeling at three
additional intersections in the Downtown area: Speer & Auraria;
Broadway & Colfax; and Broadway & Champa. These preliminary 1995
results showed predicted concentrations at Speer/Auraria and Broadway/
Colfax up to 6 ppm higher than concentrations modeled at the CAMP
monitor (Broadway & Champa). Because of uncertainties related to the
validity of meteorological inputs used in the model, the State opted
not to include the CAL3QHC modeling results for the two higher
intersections in the current SIP, deferring consideration of these
locations until additional saturation monitoring studies could be
conducted at these intersections. The State selected Broadway and
Champa as the intersection to use in the SIP attainment demonstration
because the on-site air quality and meteorology monitoring data
available at this location provided more confidence in the results,
i.e., produced modelled concentrations that were in good agreement with
concentrations actually monitored at the site. There are significant
and unique micro-meteorological effects influencing each of the three
central business district intersections, including: high-rise office
buildings, channeling of the wind down ``urban street canyons'', and
urban heat island effects. Since the Diagnostic Wind Model (DWM) used
with UAM does not include any of these effects, the State did not
consider the meteorological outputs from DWM appropriate for use in
microscale modeling.
The State's intersection analysis is consistent with national
policy and other recent UAM/CAL3QHC modeling applications. Additional
information on the attainment demonstration modeling is included in the
Technical Support Document for this action.
(2) Control Strategies
Section 172(c)(1) requires the plans for all nonattainment areas to
provide for the implementation of RACM (including RACT) as
expeditiously as practicable and to provide for attainment of the
NAAQS. The EPA interprets this requirement to impose a duty on all
nonattainment areas to consider the available control measures, and to
adopt and implement such measures as are reasonably available for
implementation in the area and necessary for attainment of the NAAQS as
components of the area's attainment demonstration. The EPA has reviewed
the State's explanation and associated documentation and concluded that
it adequately justifies the control measures to be implemented. EPA is
proposing to approve several of the control strategies. The exact
nature of EPA's proposed approvals is discussed in more detail below
and in the Technical Support Document for today's action.
The Denver CO SIP takes credit for several control programs in the
attainment demonstration. Those identified in Chapter V of the SIP as
``baseline strategies'' are measures which were in existence at the
time of CO SIP development, and for which no further State regulatory
action was required. EPA is not taking action on these control
strategies through this SIP revision, as these are strategies which
have been adopted through previous SIP revisions and have been or are
being acted on in other Federal Register documents. Those identified as
``additional control strategies'' are measures which were newly-
considered and adopted for the attainment demonstration, and which are
being acted on in this SIP revision.
The baseline strategies include the Federal motor vehicle control
program, the 2.7% oxygenated fuels program (approved in the Federal
Register on July 25, 1994 (59 FR 37698)), the Enhanced inspection and
maintenance (I/M) program (conditionally approved in the Federal
Register on November 8, 1994 (59 FR 55584)), various transportation
system improvements, and the woodburning control measures adopted as
part of the Denver PM10 SIP (approved in the Federal Register on July
25, 1994 (59 FR 37698)).
In addition, Section 246 of the Clean Air Act requires that the
State adopt and implement the Clean Fuels Fleet Program, an alternative
fuels program for certain commercial and governmental fleet operations.
AQCC Regulation 17, the Clean Fuels Fleet Program regulation, was
adopted by the AQCC on May 5, 1994, and submitted with the Denver CO
SIP. (The full Clean Fuels Fleet Program SIP was submitted to EPA on
October 17, 1994.) A wide variety of non-mandated alternative fuels
programs are also underway in the Denver area. No credit is taken for
Regulation 17 or any of the other programs in the attainment
demonstration, and EPA will act on the Clean Fuels Fleet Program in the
Federal Register at a later date.
Several additional control strategies have been formally
incorporated into or committed to in the Denver CO SIP to provide for
attainment of the CO NAAQS by December 31, 2000. These measures are
described in Chapter VI of the SIP and are discussed below.
(a) 3.1% oxygenated fuels program. In the CO SIP, the State made a
commitment, which has since been met, to implement and adopt a 3.1%
oxygenated fuels program, providing additional benefit over the 2.7%
program already required of the area by Section 211(m) of the Act. The
program is being implemented in two phases. In the winter of 1994-95, a
``maximum blending'' program took effect, which requires gasoline
suppliers using methyl tert-butyl ether as an oxygenate to blend at the
2.7% oxygen level (the maximum allowed by Federal regulations), and
suppliers using ethanol as an oxygenate to blend at the 3.5% oxygen
level (also the maximum allowed by Federal regulations). The market
share of ethanol in the Denver area has exceeded 50% in recent years,
and this approach is expected to result in at least a 3.1% oxygen
content during each winter season. If the maximum blending approach
should fail to provide for at least a 3.1% oxygen content, the SIP
provides that in subsequent winter seasons an averaging program,
pursuant to EPA guidance for such programs, will take effect.
AQCC Regulation 13 governs the oxygenated fuels program. The SIP
committed to revise this regulation in two steps. Reg 13 was revised to
incorporate the maximum blending approach for the winter of 1994-95 by
the AQCC on July 19, 1994. Reg 13 was revised to incorporate the more
complex 3.1% averaging program on October 20, 1994. Both sets of
regulation revisions were submitted by the Governor for EPA approval on
September 29, 1995. The
[[Page 36008]]
September 29, 1995 submittal was determined complete on November 30,
1995.
(b) Increased I/M failure rate for pre-1982 vehicles. The SIP
includes a commitment, which has since been met, to revise Regulation
11, which governs the I/M program, to incorporate more stringent
emissions cutpoints which will increase the failure rate for pre-1982
vehicles from the current 14-26% to approximately 40%. Pre-1982
vehicles have less advanced emission control system technology,
resulting in higher CO emission levels, and the more stringent
cutpoints for these vehicles will result in the identification and
repair of a greater number of high-emitting vehicles than are captured
by the present I/M program (an increase of approximately 70,000
vehicles per year). These regulation revisions were adopted by the AQCC
on September 22, 1994, and submitted by the Governor for EPA approval
on September 29, 1995. The September 29, 1995 submittal was determined
complete on November 30, 1995.
(c) Prohibition on the re-registration of abandoned and impounded
pre-1982 vehicles sold at auction. This element of the SIP requires
local governments in the Denver area to modify their ordinances or
procedures for disposing of pre-1982 abandoned and impounded vehicles
to prohibit purchasers from obtaining any form of title to the
vehicles. These vehicles may be sold for scrappage or dismantling only.
This measure will accelerate the normal rate of removal of vehicles of
this age from the fleet, by preventing up to 5,000 vehicles of this
type from being re-registered. Elimination of this many pre-1982
vehicles could reduce regional CO emissions by up to 5 tons per day.
However, because of the difficulty of defining a concise emission
reduction, the State does not take credit for this strategy in the
attainment demonstration.
B. Transportation Control Measures
Section 187(a)(2)(B) (Special Rule for Denver) requires the State
to submit a SIP revision that includes the TCMs as required in Section
182(d)(1)(A) of the Act, for the purpose of reducing CO emissions. The
SIP may exclude any of the Section 182(d)(1)(A) measures if 1) the SIP
includes an explanation of why any measure was not adopted and what
emission reduction measure was adopted to provide comparable reduction
in emissions, or 2) the SIP contains reasons why such reduction is not
necessary to attain the national primary ambient air quality standard
for CO.
The TCM SIP revision is contained in Chapter X of the Denver CO
SIP. The TCMs adopted as part of the SIP are listed below. See the
Technical Support Document for today's document and the SIP itself for
a more detailed description of these measures.
(1) Employer-based transportation emission management programs
promoted and encouraged by transportation management associations and
financial incentives.
(2) Auraria transit pass.
(3) Conversion of Broadway/Lincoln Bus Lanes to Bus/HOV.
(4) Improved Traffic Signalization.
(5) Other Measures.
Appendix X-A contains the State's assessment of the measures listed
in Section 108(f), including a comprehensive description of strategies
already in place in Denver and the newly-adopted measures. Several TCMs
have already been adopted as part of the SIP in previous ozone and CO
SIP revisions, and have been approved by EPA (45 FR 51199, August 1,
1980, and 48 FR 55284, December 12, 1983). Appendix X-A also describes
projects and programs which are not being included in the SIP but
nevertheless provide some emission reduction benefit.
EPA is proposing to approve this element of the Denver CO SIP. The
SIP satisfies the requirement of Section 187(a)(2)(B) to either include
the TCMs or provide a justification for not including them. The
attainment demonstration for the SIP does not include credit for any of
the TCMs; however, the above measures were adopted as enforceable
provisions of the SIP.
C. Vehicle Miles Traveled Forecasting and Tracking
Section 187(a)(2)(A) of the Clean Air Act Amendments of 1990
required EPA, in consultation with the U.S. Department of
Transportation (DOT), to develop guidance for states to use in
complying with the VMT forecasting and tracking provisions of Section
187. A Notice of Availability for the resulting Section 187 VMT
Forecasting and Tracking Guidance was published in the Federal Register
on March 19, 1992. Section 187(a)(2)(A) requires Denver to submit a SIP
revision providing for a VMT forecasting and tracking program, and
contingency measures for implementation in the event that a VMT
forecast is exceeded. The specific requirements are discussed in detail
in the Technical Support Document for today's action.
The State of Colorado has submitted a SIP revision to EPA in order
to satisfy the requirements of Section 187(a)(2)(A) and Section
187(a)(3). In order to gain approval, the State submittal must provide
for each of the following mandatory elements: (1) a forecast of VMT in
the non-attainment area for each year prior to the attainment year; (2)
a provision for annual updates of the forecasts along with a provision
for annual reports describing the extent to which the forecasts proved
to be accurate; these reports shall provide estimates of actual VMT in
each year for which a forecast was required; (3) adopted and
enforceable contingency measures to be implemented without further
action by the State or the Administrator if actual annual VMT or an
updated forecast exceeds the most recent prior forecast or if the area
fails to attain the CO NAAQS by the attainment date.
(1) VMT Forecasts
Section 187(a)(2)(A) requires that the State include in its SIP
submittal a forecast of VMT in the non-attainment area for each year
before the year in which the SIP projects the National Ambient Air
Quality Standard for CO will be attained. The forecasts are to be based
on guidance developed by EPA in consultation with DOT, i.e., the
Section 187 VMT Forecasting and Tracking Guidance. Table XIV-2 of the
SIP contains the required forecasts of annual VMT for the years 1993-
2001.
(2) Annual VMT Updates/Reports
Section 187(a)(2)(A) specifies that the SIP revision provide for
annual updates of the VMT forecasts and annual reports that describe
the accuracy of the forecasts and that provide estimates of actual VMT
in each year for which a forecast was required. The Section 187 VMT
Forecasting and Tracking Guidance specifies that annual reports should
be submitted to EPA by September 30 of the year following the year for
which the VMT estimate is made. The SIP commits to the submission of
these annual reports and identifies responsibilities among the various
transportation agencies in Denver to develop the reports.
(3) Contingency Measures
Section 187(a)(3) specifies that the State, in its SIP revision,
adopt specific, enforceable contingency measures to be implemented if
the annual estimate of actual VMT or a subsequent VMT forecast exceeds
the most recent prior forecast of VMT or if the area fails to attain
the CO NAAQS by the attainment date. Implementation of the identified
contingency measures must not require further rulemaking activities by
the
[[Page 36009]]
State or EPA. Certain actions, such as notification of sources, would
probably be needed before a measure could be implemented effectively.
The State has met this requirement, as discussed in Section D. below.
The State of Colorado has submitted a SIP revision implementing each of
the required elements required by Section 187(a)(2)(A) and Section
187(a)(3) of the CAAA.
D. Contingency Measures
The Clean Air Act requires each CO nonattainment area with a design
value above 12.7 ppm at the time of classification to adopt contingency
measures that will take effect without further action by the State or
EPA upon a determination by EPA that an area failed to make reasonable
further progress or to attain the standards, as described in
Sec. 172(c)(9), or that actual or forecasted VMT exceeded a previous
forecast. Section 187(a)(3) requires the State to submit a SIP revision
containing contingency measures no later than November 15, 1992. The
State submitted these measures as part of the Denver CO SIP on July 11,
1994.
States may implement contingency measures early to obtain
additional emission reductions, without being required to adopt
replacement contingency measures to put in place should one of the
triggering events for implementation of contingency measures occur.
This policy is described in a memorandum from Tom Helms, Chief of the
OAQPS Ozone Policy and Strategies Group entitled ``Early Implementation
of Contingency Measures for Ozone and Carbon Monoxide Nonattainment
Areas,'' August 13, 1993.
As noted above, the State did not take credit in the attainment
demonstration for the TCMs adopted to meet the requirements of Section
187(a)(2)(B). Because these measures are surplus to the reductions
needed for attainment, the State has adopted these as the required
contingency measures as well. The Denver region is proceeding with
early implementation of these measures to obtain the additional
emission reductions they provide.
If a triggering event for contingency measures occurs, EPA will
review the status of implementation of the TCMs adopted in Chapter X of
the SIP. Each of the TCMs must be fully implemented in order to satisy
the contingency measures requirements of Sections 172 and 187. In
addition, the EPA/DOT transportation conformity regulation (58 FR
62235, November 24, 1993) requires DRCOG and USDOT to demonstrate that
SIP TCMs are being implemented or are on schedule for implementation
before making a conformity determination for transportation plans or
TIPs. This provides an extra degree of assurance that the contingency
measures will be implemented if needed.
Section XIII.C. of the SIP defines the target emissions reduction
level for contingency measures. Based on average projected annual VMT
growth between 1995 and 2000 and the modeled fleet emission factors for
those years, the State determined that minimum emission reductions of
26 tons per day in 1995 and 16 tons per day in 2000 represented the
minimum emission reduction levels for contingency measures pursuant to
EPA guidance. The TCMs, when fully implemented, are projected to
produce an emission reduction of 34 tons per day in the year 2000. The
emission reductions would be higher in earlier years, since the
baseline fleet emission factors to which the contingency measure
effectiveness would be applied are higher. Thus, the submittal
satisfies EPA's minimum criteria for contingency measure effectiveness.
E. Mobile Source Emissions Budgets and Transportation Conformity
Section 176(c)(1) of the Act directs that no department, agency, or
instrumentality of the federal government may permit any activity that
does not conform to a SIP. Section 176(c)(2) further specifies that
federally funded transportation improvement programs (TIPs), regional
transportation plans, and projects must conform to the SIP in order to
be adopted by the metropolitan planning organization. EPA and DOT
promulgated implementing regulations for this CAA provision on November
24, 1993 (58 FR 62235).
One key provision of the conformity regulations requires a
demonstration that emissions from the transportation plan and TIP are
consistent with the emissions budget in the SIP (Sections 93.118 and
93.119 of the conformity rule). The emissions budget is defined as the
level of mobile source emissions relied upon in the attainment and/or
maintenance demonstration to achieve compliance with the NAAQS in the
nonattainment area. The rule's requirements and EPA's policy on
emissions budgets are found in the Preamble to the transportation
conformity rule (58 FR 62193-96) and in the sections of the rule
referenced above. The SIP defines emissions budgets for the 1995
milestone year and the 2000 attainment year.
The 1995 budget is consistent with the mobile source emissions
estimate for the milestone year and is 1125 tons per day in the
nonattainment area. This budget no longer applies for conformity, since
that date has passed. For the year 2000, the SIP includes modeling for
scenarios with and without TCMs. The RAQC recommended that the AQCC
adopt the emissions budget for the scenario without TCMs as the budget
to be used for conformity (825 tons per day in the nonattainment area).
However, the AQCC adopted (and the Governor submitted) an emission
budget of 808 tons per day in the nonattainment area. This lower budget
reflected some (not all) of the emissions reductions associated with
the implementation of the TCMs. The AQCC felt that this lower budget
would provide a margin of safety for attainment and would provide an
extra incentive (through the conformity requirements) for
implementation of the TCMs.
Subsequent to submittal of the SIP, DRCOG completed an initial
conformity analysis for the 2015 transportation plan and the 1995-2000
TIP, and found that the plan and TIP could not conform to the lower
budget adopted by the AQCC and submitted to EPA. In response, the RAQC
adopted a resolution requesting that the AQCC revise the SIP to raise
the emission budget to the attainment level of 825 tons per day. The
AQCC adopted this SIP revision after a public hearing on February 16,
1995, and the Governor submitted this SIP revision on July 18, 1995.
The Governor's July 18, 1995 letter withdraws the 808 ton per day
emission budget submitted on July 11, 1994. This leaves the default
budget of 825 tons per day from the attainment demonstration as the
applicable budget under EPA's conformity rule. Since EPA is proposing
to approve the attainment demonstration, the 825 ton per day budget
that the attainment demonstration is based on would be approved by
default, and no separate action is necessary on the July 18, 1995
submittal of this budget.
Section 93.106(b) of the conformity rule requires that the
transportation plans in moderate nonattainment areas reclassified to
serious meet certain content and analysis requirements. These new
requirements would affect plans adopted two years after
reclassification to serious. Once EPA reclassifies the Denver area to
serious, these requirements will take effect two years thereafter.
DRCOG's transportation planning methodologies already meet many of
these requirements.
[[Page 36010]]
Longmont
A. Background of Sip Revision
Pursuant to the requirements of the 1990 Clean Air Act Amendments,
each State was required to identify its nonattainment areas and submit
descriptions of these areas for EPA promulgation in 40 CFR Part 81.
Longmont had been designated as unclassifiable/attainment prior to
passage of the 1990 Amendments. However, a special monitoring study in
1988-89 recorded an exceedance of the NAAQS in Longmont. (This study is
described in Chapter II of the Longmont SIP.) As a result, EPA Region
VIII recommended that the Governor designate this area nonattainment in
a letter dated January 15, 1991. In a letter dated March 15, 1991,
Governor Roy Romer submitted a request that Longmont be designated a
moderate nonattainment area, and submitted boundaries for the new area.
The designation, classification and boundaries were promulgated by EPA
in the Federal Register on November 6, 1991 (56 FR 56733).
Since this area had never had a SIP, EPA interpreted Section 172 of
the Act to require an attainment demonstration for Longmont. As a
moderate area, the applicable attainment date for Longmont is December
31, 1995. Contingency measures under Section 172(b)(9) were also
required. On January 15, 1993, EPA made a formal finding that the State
had failed to submit these SIP revisions for Longmont.
On July 13, 1994, Governor Roy Romer submitted comprehensive
revisions to the Colorado SIP. The carbon monoxide SIP element
submittal for Longmont addressed the outstanding CAA requirements
discussed above, as well as other CAA mandates. EPA found this SIP
element complete on July 14, 1994. The CO SIP revision for Longmont was
developed primarily by APCD, in consultation with the City of Longmont.
The SIP development process is discussed in Chapter I of the SIP.
Throughout the remainder of this Federal Register document,
references are made to the ``Longmont area.'' This is a matter of
convenience; these references apply to the Longmont CO nonattainment
area as defined in 40 CFR Part 81 unless otherwise noted.
B. Attainment Demonstration and Control Strategies: Longmont
(1) Attainment Demonstration
A different approach was used for demonstrating attainment in
Longmont than the methodology used in Denver. Originally, the State
planned to develop the attainment demonstration for Longmont as part of
the modeling for Denver. However, it was discovered that the ambient
conditions which led to exceedances of the CO NAAQS in Denver were not
directly applicable to Longmont. After reviewing the results of the
1988-89 special monitoring studies, which suggested that exceedances
occur due to emissions on a neighborhood scale, and in consideration of
Longmont's small size and low traffic counts relative to conditions in
Denver, EPA concluded that the complex UAM/CAL3QHC modeling methodology
used in Denver was not necessary for demonstrating attainment in
Longmont. EPA recommended that a simple rollforward analysis, similar
to that used in attainment demonstrations for Colorado's smaller PM10
nonattainment areas, be used for Longmont. This decision is documented
in a July 26, 1993 letter from EPA to APCD.
The methodology used and the results are presented in Chapter IV of
the SIP. The SIP projects a second maximum concentration of 6.97 ppm at
the end of 1995, well below the 9.0 ppm NAAQS.
(2) Control Strategies
Section 172(c)(1) of the Act requires the plans for all
nonattainment areas to provide for the implementation of RACM
(including RACT) as expeditiously as practicable and to provide for
attainment of the NAAQS. EPA interprets this requirement to impose a
duty on all nonattainment areas to consider the available control
measures, and to adopt and implement such measures as are reasonably
available and necessary for attainment of the NAAQS as components of
the area's attainment demonstration. EPA has reviewed the State's
explanation and associated documentation and concluded that it
adequately justifies the control measures being implemented.
The Longmont CO SIP takes credit for several control programs in
the attainment demonstration. These control strategies, identified in
Table III.3 and discussed in Chapter V of the SIP, are measures which
were in existence at the time of CO SIP development, and for which no
further State regulatory action was required. EPA is not taking action
on these control strategies in this Federal Register document, as these
are strategies which have been adopted through previous SIP revisions
and have been or are being acted on in other Federal Register
documents. The attainment demonstration does not take credit for any
newly-adopted control strategies, nor are any such strategies included
in the SIP. In addition, Chapter V discusses several other activities
underway in the Longmont area that have emission reduction benefits.
However, these activities are not identified as control strategies and
are not reflected in the 1995 attainment emission inventory, and thus,
EPA is not incorporating these measures into the SIP.
The control strategies relied upon for the Longmont attainment
demonstration include the Federal motor vehicle control program, the
2.7% oxygenated fuels program (approved in the Federal Register on July
25, 1994 (59 FR 37698)), the enhanced inspection and maintenance (I/M)
program (conditionally approved in the Federal Register on November 8,
1994 (59 FR 55594)), various ongoing travel reduction strategies and
transportation system improvements, and woodburning control measures
from the Denver PM10 SIP (the woodburning program was approved in the
Federal Register on July 25, 1995 (59 FR 37698)).
The package of strategies incorporated in the attainment
demonstration is expected to reduce emisssions from 55.070 tons per day
in 1988 to 37.292 tons per day in 1995, for an overall reduction of
approximately 32%. The strategies result in a 1995 projected second
maximum concentration of 6.97 ppm.
C. Contingency Measures: Longmont
EPA's requirements for contingency measures are described above.
Unlike Denver, Longmont is not subject to the CAA Section 187(a)(2)(A)
requirement for a VMT forecasting and tracking program, and thus is not
required to implement contingency measures in the event that a VMT
forecast is exceeded. Contingency measures for Longmont were submitted
as part of the July 13, 1994 SIP.
The 3.1% oxygenated fuels program, adopted as part of the Denver CO
SIP, has been adopted as the contingency measure for Longmont. This
measure is being implemented in the entire six-county Denver
metropolitan area as required by the Clean Air Act, and thus is being
implemented in Longmont, even though it is not credited in the
attainment demonstration. EPA considers this to be early implementation
of the contingency measure, as provided for in the August 13, 1993 Tom
Helms memorandum referenced above.
Section V.C. of the SIP defines the target emissions reduction
level for contingency measures. VMT growth in Longmont was estimated at
3.1% per
[[Page 36011]]
year, which equates to CO emissions growth of 0.92 tons per year. The
3.1% oxygenated fuels program gives Longmont an additional incremental
emission reduction over the 2.7% program of 1.01 tons per year, which
exceeds the minimum emission reduction level. Thus, EPA's minimum
requirements for contingency measures are satisfied by the State's
submittal.
II. Implications of This Action
In today's action, EPA is proposing to approve SIP revisions
submitted by the Governor on July 11, 1994, July 13, 1994, and
September 29, 1995. Specifically, EPA is proposing to (1) approve the
July 11, 1994 attainment demonstration, VMT tracking and forecasting
program, TCM, and contingency measures submittals for Denver; (2)
approve the July 13, 1994 attainment demonstration and contingency
measures submittals for Longmont; and (3) approve the control
strategies for Denver, including the September 29, 1995 submittal of
revisions to Regulations 11 and 13 (I/M and oxygenated fuels).
In this document, EPA is also proposing to find that the Denver/
Boulder carbon monoxide nonattainment area did not attain the NAAQS by
the required attainment date of December 31, 1995, and to revise the
area's classification for carbon monoxide in 40 CFR Part 81 from
moderate to serious. This proposed finding is based on air quality data
revealing more than one exceedance of the CO NAAQS during calendar year
1995, resulting in a design value higher than the NAAQS for the period
1994-95. By action dated December 20, 1994, the EPA Administrator
delegated to the Regional Administrators the authority to determine
whether CO nonattainment areas attained the NAAQS, and to reclassify
those that did not.
III. Request for Public Comments
EPA is requesting comments on all aspects of today's proposal. As
indicated at the outset of this document, EPA will consider any
comments received by August 8, 1996.
IV. Executive Order (EO) 12866
Under EO 12866, 58 FR 51735 (October 4, 1993), EPA is required to
determine whether regulatory actions are significant and therefore
should be subject to OMB review, economic analysis, and the
requirements of the EO. The EO defines a ``significant regulatory
action'' as one that is likely to result in a rule that may meet at
least one of the four criteria identified in section 3(f) of the EO,
including, under paragraph (1), that the rule may ``have an annual
effect on the economy of $100 million or more or adversely affect, in a
material way, the economy, a sector of the economy, productivity,
competition, jobs, the environment, public health or safety, or State,
local, or tribal governments or communities.''
The SIP-related actions proposed today have been classified as
Table 3 actions for signature by the Regional Administrator under the
procedures published in the Federal Register on January 19, 1989 (54 FR
2214-2225), as revised by a July 10, 1995 memorandum from Mary Nichols,
Assistant Administrator for Air and Radiation. The Office of Management
and Budget has exempted these regulatory actions from EO 12866 review.
Likewise, EPA has determined that the finding of failure to attain
proposed today would result in none of the effects identified in
section 3(f) of the EO. Under Section 186(b)(2) of the Clean Air Act,
findings of failure to attain and reclassification of nonattainment
areas are based upon air quality considerations and must occur by
operation of law in light of certain air quality conditions. They do
not, in and of themselves, impose any new requirements on any sectors
of the economy. In addition, because the statutory requirements are
clearly defined with respect to the differently classified areas, and
because those requirements are automatically triggered by
classifications that, in turn, are triggered by air quality values,
findings of failure to attain and reclassification cannot be said to
impose a materially adverse impact on State, local, or tribal
governments or communities.
V. Regulatory Flexibility
Under the Regulatory Flexibility Act, 5 U.S.C. section 600 et.
seq., EPA must prepare a regulatory flexibility analysis assessing the
impact of any proposed or final rule on small entities (5 U.S.C.
sections 603 and 604). Alternatively, EPA may certify that the rule
will not have a significant impact on a substantial number of small
entities. Small entities include small businesses, small not-for-profit
enterprises, and government entities with jurisidiction over
populations that are less than 50,000.
SIP revision approvals under Section 110 and Subchapter I, Part D,
of the CAA do not create any new requirements, but simply approve
requirements that the State is already imposing. Therefore, because the
Federal SIP approval process does not impose any new requirements, EPA
certifies that this proposed rule would not have a significant impact
on any small entities affected. Moreover, due to the nature of the
Federal-State relationship under the CAA, preparation of a regulatory
flexibility analysis would constitute Federal inquiry into the economic
reasonableness of State actions. The CAA forbids EPA to base its
actions concerning SIPs on such grounds. Union Electric Co. v.
U.S.E.P.A., 427 U.S. 246, 256-266 (S. Ct. 1976); 42 U.S.C. section
7410(a)(2).
As discussed in section IV. of this document, findings of failure
to attain and reclassification of nonattainment areas under Section
186(b)(2) of the CAA do not, in and of themselves, create any new
requirements. Therefore, I certify that today's proposal does not have
a significant impact on small entities.
VI. Unfunded Mandates
Under Section 202 of the Unfunded Mandates Reform Act of 1995
(``Unfunded Mandates Act''), signed into law on March 22, 1995, EPA
must prepare a budgetary impact statement to accompany any proposed or
final rule that includes a Federal mandate that may result in estimated
costs to State, local, or tribal governments in the aggregate, or to
the private sector, of $100 million or more. Under Section 205, EPA
must select the most cost-effective and least burdensome alternative
that achieves the objectives of the rule and is consistent with
statutory requirements. Section 203 requires EPA to establish a plan
for informing and advising any small governments that may be
significantly or uniquely impacted by the rule.
EPA has determined that the SIP approval actions proposed today do
not include a Federal mandate that may result in estimated costs of
$100 million or more to either State, local or tribal governments in
the aggregate, or to the private sector. These Federal actions approve
pre-existing requirements under State or local law, and impose no new
Federal requirements. Accordingly, no additional costs to State, local
or tribal governments, or to the private sector, result from these
actions.
Likewise, EPA believes, as discussed in section IV of this
document, that the proposed finding of failure to attain and
reclassification to serious are factual determinations based upon air
quality data and must occur by operation of law and, hence, do not
impose any federal intergovernmental mandate, as defined in section 101
of the Unfunded Mandates Act.
[[Page 36012]]
List of Subjects
40 CFR Part 52
Environmental protection, Air pollution control, Carbon monoxide,
Intergovernmental relations, Reporting recordkeeping requirements.
40 CFR Part 81
Air pollution control.
Authority: U.S.C. 7401-7671q.
Dated: June 24, 1996.
Jack W. McGraw,
Acting Regional Administrator.
[FR Doc. 96-17319 Filed 7-8-96; 8:45 am]
BILLING CODE 6560-50-P
