[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.<SUP>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/
m<SUP>3) and the 8-hour CO NAAQS is 9 ppm (10 mg/m<SUP>3). 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