Clean Air Act Approval and Promulgation of PMINF10 Implementation Plan for Denver, CO

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[CO-001-0016; FRL-5802-6]

Clean Air Act Approval and Promulgation of PM10

Implementation Plan for Denver, CO

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: EPA is approving the State Implementation Plan (SIP) revisions

submitted by the Governor of Colorado for the purpose of bringing about

the attainment of the national ambient air quality standards (NAAQS)

for particulate matter with an aerodynamic diameter less than or equal

to a nominal 10 micrometers (PM10) in the Denver area. The SIP

revisions were submitted to satisfy certain Federal requirements for an

approvable moderate nonattainment area PM10 SIP for Denver and,

among other things, contain enforceable control measures. The bulk of

the revisions were submitted on March 30, 1995. Revisions to Colorado

Regulation No. 13 (oxygenated fuels), which is one of the control

measures relied on in the SIP, were adopted by the Air Quality Control

Commission

[[Page 18717]]

(AQCC) on October 19, 1995 and submitted to EPA on December 22, 1995.

EPA proposed to approve the March 30, 1995 submission on October 3,

1996. On December 6, 1996, EPA published a supplemental proposal to

approve the Denver PM10 SIP based on the October 19, 1995 version

of Regulation No. 13 rather than the prior version. This action

supersedes EPA's July 25, 1994, final limited approval of certain

control measures found in the State's June 7, 1993 Denver PM10 SIP

submittal.

DATES This action will become effective on May 19, 1997.

ADDRESSES: Copies of the State's submittal 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;

Colorado Air Pollution Control Division, 4300 Cherry Creek Dr. South,

Denver, Colorado 80222-1530; and the Air and Radiation Docket and

Information Center, 401 M Street, SW, Washington, D.C. 20460.

FOR FURTHER INFORMATION CONTACT: Callie Videtich at (303) 312-6434.

SUPPLEMENTARY INFORMATION:

I. Background

The Denver, Colorado area was designated nonattainment for

PM10 and classified as moderate under sections 107(d)(4)(B) and

188(a) of the Act, upon enactment of the Clean Air Act Amendments of

1990.1 See 56 FR 56694 (Nov. 6, 1991) and 40 CFR 81.306

(specifying PM10 nonattainment designation for the Denver

metropolitan area). The air quality planning requirements for moderate

PM10 nonattainment areas are set out in Part D, Subparts 1 and 4,

of Title I of the Act. 2

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\1\ The 1990 Amendments to the Clean Air Act made significant

changes to the Act. See Pub. L. No. 101-549, 104 Stat. 2399.

References herein are to the Clean Air Act, as amended (``the

Act''). The Clean Air Act is codified, as amended, in the U.S. Code

at 42 U.S.C. 7401, et seq.

\2\ Subpart 1 contains provisions applicable to nonattainment

areas generally and Subpart 4 contains provisions specifically

applicable to PM10 nonattainment areas. At times, Subpart 1 and

Subpart 4 overlap or conflict. EPA has attempted to clarify the

relationship among these provisions in the ``General Preamble'' and,

as appropriate, in today's notice and supporting information.

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The EPA has issued a ``General Preamble'' describing EPA's

preliminary views on how EPA intends to review SIPs and SIP revisions

submitted under Title I of the Act, including those State submittals

containing moderate PM10 nonattainment area SIP requirements (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 this

action and the supporting rationale. In this rulemaking action on the

Colorado moderate PM10 SIP for the Denver nonattainment area, EPA

is applying its interpretations considering the specific factual issues

presented.

Those States containing initial moderate PM10 nonattainment

areas (those areas designated nonattainment under section 107(d)(4)(B)

of the Act) were required to submit, among other things, the following

plan provisions by November 15, 1991:

1. Provisions to assure that reasonably available control measures

(RACM) (including such reductions in emissions from existing sources in

the area as may be obtained through the adoption, at a minimum, of

reasonably available control technology (RACT)) shall be implemented no

later than December 10, 1993;

2. Either a demonstration (including air quality modeling) that the

plan will provide for attainment as expeditiously as practicable but no

later than December 31, 1994, or a demonstration that attainment by

that date is impracticable;

3. Quantitative milestones which are to be achieved every 3 years

and which demonstrate reasonable further progress (RFP) toward

attainment by December 31, 1994; and

4. Provisions to assure that the control requirements applicable to

major stationary sources of PM10 also apply to major stationary

sources of PM10 precursors except where the Administrator

determines that such sources do not contribute significantly to

PM10 levels which exceed the NAAQS in the area. See sections

172(c), 188, and 189 of the Act.

Some provisions were due at a later date. States with initial

moderate PM10 nonattainment areas were required to submit a new

source review (NSR) permit program for the construction and operation

of new and modified major stationary sources of PM10 by June 30,

1992 (see section 189(a)). On January 14, 1993, the State submitted

regulation revisions for the construction of new and modified major

stationary sources. On August 18, 1994, EPA partially approved the

State's NSR program for the Denver PM10 nonattainment area because

the State had not yet submitted NSR provisions for sources of PM10

precursors (i.e., NOX and SO2) in the Denver area (see 59 FR

42300). On August 25, 1994, Colorado submitted additional NSR

provisions for precursor emissions. EPA took final action on that SIP

submittal on January 21, 1997 (62 FR 2910). Thus, the State has a

fully-approved NSR permitting program in place for the Denver moderate

PM10 nonattainment area.

States were also required to submit contingency measures for

PM10 moderate nonattainment areas by November 15, 1993. The

contingency measures for the Denver PM10 nonattainment area were

initially submitted by the Governor on December 9, 1993. However, those

control measures were later incorporated into the revised March 30,

1995 PM10 SIP to help demonstrate attainment and maintenance.

Thus, the State developed new contingency measures, and on November 17,

1995, the Governor submitted those measures to EPA. EPA took direct

final rulemaking action on the contingency measures SIP submittal on

September 23, 1996 (61 FR 49682). Because no adverse comments were

received for the direct final rulemaking, the rule became effective on

December 23, 1996.

On June 7, 1993, the Governor submitted a SIP for Denver to EPA

which was intended to satisfy those elements due November 15, 1991. On

December 20, 1993, EPA proposed to conditionally approve that SIP and

also proposed to approve the SIP's control measures for their limited

purpose of strengthening the Colorado SIP (58 FR 66326). On July 25,

1994, EPA granted limited approval of the control measures for the

limited purpose of strengthening the SIP (59 FR 37698).

During review of the technical information supporting the June 1993

SIP, EPA examined information which raised concerns about the accuracy

of the SIP's attainment demonstration. The SIP's technical support

documentation suggested that the contribution from PM10

``precursors'' (i.e., NOX and SO2) in the base year winter

season may have been underestimated. Since the attainment demonstration

provided with that SIP predicted a value of 149.9 g/m3

over 24 hours, virtually any increase in precursor PM10 levels

would result in predicted violations of the 24-hour standard.

In the December 20, 1993, proposed rulemaking action, EPA requested

public comment on its proposal to grant conditional approval of the SIP

in light of the precursor issue. EPA reviewed the information submitted

during the public comment period and concluded that precursors were

underestimated by 5.4 g/m.\3\ Based upon this finding, EPA

[[Page 18718]]

delayed taking final action on the proposed conditional approval to

allow the State an opportunity to develop additional controls to offset

this increase. EPA never proceeded with the conditional approval. On

March 30, 1995, the Governor submitted a SIP revision intended to

provide controls to offset the increase in precursor emissions and

provide credible attainment and maintenance demonstrations. Based on

this SIP revision, EPA proposed approval of the PM10 SIP on

October 3, 1996 (61 FR 51631).

On July 18, 1995, and April 22, 1996, the Governor submitted

additional revisions to the SIP which establish mobile source emissions

budgets for PM10 and NOX. These budgets are used under EPA

regulations for making transportation related conformity determinations

as required by section 176(c) of the Act. EPA's transportation

conformity rule provides that these budgets establish a cap on motor

vehicle-related emissions which cannot be exceeded by the predicted

transportation system emissions in the future unless the cap is amended

by the State and approved by EPA as a SIP revision and attainment and

maintenance of the standard can be demonstrated. EPA proposed approval

of these emissions budgets on October 3, 1996 along with the Denver

PM10 SIP. However, EPA is not taking final action on the two

emissions budgets in order to more thoroughly consider comments

received during the public comment period. These emissions budgets are

not necessary to meet the Act's requirements for moderate PM10

nonattainment areas and, therefore, will be addressed in a separate

rulemaking.

EPA became aware after proposing approval of the PM10 SIP that

the version of Regulation No. 13 (oxygenated fuels) that was one of the

control measures relied on in the Denver PM10 SIP had been

replaced by the October 19, 1995 version of Regulation No. 13. The

Governor submitted this version to EPA as a SIP revision on December

22, 1995. The October 19, 1995 version eliminates the last two weeks

from the program and calls for a 3.1% program rather than a 2.7%

program. On December 6, 1996 (61 FR 64647) EPA published a supplemental

document that, among other things, proposed to approve the Denver

PM10 SIP with the October 19, 1995 version of Regulation No. 13

substituted for the prior version. EPA received no comments regarding

this aspect of the supplemental document and is proceeding with its

approval of the Denver PM10 SIP based on the October 19, 1995

version of Regulation No. 13.

EPA has already approved the October 19, 1995 version of Regulation

No. 13 as part of the Denver carbon monoxide (CO) SIP. The acting

Regional Administrator for EPA Region VIII signed a Federal Register

document approving the Denver CO SIP on January 31, 1997, but at the

time this document was prepared, that approval had not yet been

published in the Federal Register.

II. Response to Public Comments

EPA received numerous comments on its proposed approval of the

Denver PM10 SIP and the PM10 and NOX emissions budgets.

In this document, EPA is addressing only those comments submitted on

the Denver PM10 SIP. The comments received regarding the emissions

budgets will be addressed in a later rulemaking action. The comments

received on the Denver PM10 SIP and EPA's responses follow.

1. The SIP revision fails to contain control measures to limit

motor vehicle emissions from current vehicle miles traveled (VMT) or

revised projections of VMT growth and does not provide for attainment.

As EPA noted in its approval of the Denver CO SIP, the Denver

Regional Council of Governments (DRCOG) produced revised estimates of

daily vehicle miles traveled in the summer and fall of 1996. In early

1996, DRCOG made some improvements to its transportation demand model

(used for transportation planning, and to produce estimates of future

VMT and speeds for air quality planning purposes) and validated the

model with actual 1995 traffic counts recorded in Denver. These

adjustments led to revised estimates of approximately 49 million miles

per day of traffic in the Denver area (the previous modeled estimate

had been approximately 45 million miles per day). The commentor

referred to these revised estimates and suggested that EPA should

disapprove the SIP on this basis, or conditionally approve the SIP and

request that the State submit additional controls.

EPA believes that the increases in VMT are not sufficient to

warrant revisions to the PM10 SIP or its disapproval. EPA believes

that it is reasonable to allow some margin of error for VMT projections

in attainment demonstrations. This is because these projections are by

their nature inexact. For CO SIPs, EPA has recognized this in the

General Preamble and other guidance (see 57 FR 13532 and Section 187

VMT Forecasting and Tracking Guidance, January 1992). EPA applied these

policies in its approval of the Denver CO SIP and believes it is

reasonable to extend them to the Denver PM10 SIP.

It must be emphasized that only part of the estimated VMT increase

is due to actual growth in traffic in the Denver region; the rest is

due to use of improved methodologies for traffic counting in the

region. For this reason, EPA believes it is more appropriate to

consider the impact of actual growth in VMT by examining counts based

on a consistent methodology, that is, the HPMS-based VMT Tracking

Program. In November 1996, Colorado submitted its 1996 report of 1995

actual annual VMT, as required by section 187 of the Act for CO SIPs.

This report showed that actual 1995 VMT were 4.4% greater than the CO

SIP projections and 1.3% greater than the most recent revised

projection for 1995. These exceedances are within the allowable limits

of EPA's VMT Tracking Program guidance for CO SIPs (5.0% and 3.0% for

the respective VMT projections). EPA established these tolerances in

recognition of the uncertainty inherent in attempting to measure actual

VMT in a large urban area. Since the most recent reported actual annual

VMT is within these allowable tolerances, EPA is not requiring the

State to revise either the CO or PM10 SIPs.

One other factor that should be noted is that virtually all of the

growth in the metro area has occurred not in the downtown area, where

the violations of the NAAQS have been monitored, but in outlying

portions of the metro area. Thus, EPA would expect that VMT in the

downtown area would increase at a lower rate than VMT for the metro

area as a whole. This is supported by traffic counts at locations near

downtown, which show that traffic in the central area increased at a

rate of approximately 2-3% per year between 1990 and 1995, even though

DRCOG estimates that traffic has increased approximately 4.5% per year

region wide.

2. Enforceability requirements of the Act are not satisfied for

some control measures. EPA and the State lack enforcement authority for

woodburning control measures relied on in the SIP.

The commentor indicates that although the State's woodburning

program requires that certification programs for new or replaced stoves

be enforced through local building codes, there is no provision for

enforcement by the State in the event the local government fails to

adopt the certification requirement or fails to enforce the code. In

fact, Regulation No. 4, Section II.A, prohibits the sale of wood stoves

that do not meet the

[[Page 18719]]

emission standards of 40 CFR 60.532(b)(1) or (2). There is no exemption

in the regulation for areas with local prohibitions. Thus, the State

has the ability to directly enforce the certification program for

woodburning stoves. And, because this provision will be part of the

SIP, EPA and citizens will also be able to enforce it.

For new and remodeled woodburning fireplaces, it is true that local

building codes and ordinances serve as the primary mechanism for

implementation and enforcement. However, Section VIII of Regulation No.

4 requires the local jurisdictions to implement and enforce the local

codes and ordinances. The State has the authority to enforce this

requirement for implementation and enforcement. (See 25-7-115(l)(a),

C.R.S.) Because this requirement is being approved by EPA, EPA and

citizens will also have the ability to enforce it. Also, it appears

that because these local codes and ordinances have been adopted as part

of the SIP, the State may have the ability to enforce them directly

pursuant to 25-7-128(l), C.R.S. EPA is approving them as part of the

SIP, which will enable EPA and citizens to enforce them.

For any local jurisdiction that has not adopted the relevant

provisions for fireplaces into a building code or ordinance as of

January 1, 1993, Section VII.A of Regulation No. 4 prohibits the

installation of a fireplace unless it is of a type specified in Section

VII.A. The State may enforce this requirement. Because EPA is approving

this requirement, EPA and citizens will also have the ability to

enforce it.

3. VMT reduction measures are not adopted measures and are not

enforceable.

One commentor mentioned that several programs and projects

administered by the Regional Transportation District (RTD) in Denver

were included in the SIP modeling, but were not adopted as

transportation control measures and/or made enforceable. These projects

include RTD's MAC light rail line, bus service to Denver International

Airport, and three discount/free bus pass programs. All of these

programs have been implemented, and the SIP's assumption that these

activities would continue to be implemented seems reasonable to EPA.

The MAC light rail line is a vital transportation link to downtown and

serves as the starting point for a second line proceeding down the

southwest corridor, which has been approved and is under development,

and a proposed third line in the southeast corridor, which is currently

being evaluated as part of a Major Investment Study in that corridor.

Bus service to the airport has been implemented, and there are no

current plans to discontinue it. The discount bus pass programs

mentioned in the SIP have proven quite popular, helping to ensure their

continuation. It seems more reasonable for the SIP to assume that these

RTD activities would continue than to assume they would be terminated.

States are authorized to base SIP emission inventories on

reasonable assumptions regarding the makeup of the transportation

network in future years. Most of the inputs to the transportation

modeling process represent informed assumptions, including the extent

and location of population and employment, speeds, mode choice, and

participation in trip-reduction activities. The impacts of these

assumptions by their nature are impractical to make enforceable; there

are no mechanisms through which the SIP can force population growth to

occur in one area and not another, or can force citizens to participate

in carpools or ride the bus. Likewise, assumptions about the future

transportation network are reflected in the transportation data used to

generate the inventory, but are not practical to make enforceable. Each

transportation project in the transportation plan and Transportation

Improvement Program (TIP) would have to be included in the SIP, and the

SIP would have to be revised each time a new plan and TIP were

generated. Also, many projects which do not reduce VMT still have a

localized benefit for air quality such as the E470 beltway, which

reduces CO in the central metro area. However, it would be

inappropriate to include a VMT- and emissions-generating project like

E470 in an SIP as a control measure.

4. Modeling. One commentor criticized the accuracy of DRCOG's

transportation modeling, and cited concerns from Environmental Defense

Fund's Michael Replogle. The commentor did not supply a copy of Mr.

Replogle's testimony and EPA does not have it in its possession. Thus,

EPA has no basis to respond to specific concerns Mr. Replogle might

have had. However, EPA believes the transportation modeling for the SIP

was adequate and consistent with EPA guidance. EPA's guidance

(Procedures for Preparing Emissions Projections, EPA-450/4-91-019, July

1991) establishes minimum criteria for network modeling which DRCOG has

met. In fact, DRCOG has exceeded guidance requirements, which would

allow the use of less robust methods than network modeling. For

example, the New York City CO SIP (which EPA has also approved) was not

based on network modeling. EPA's guidance generally advises states to

use the best tools they have available. Neither EPA's inventory nor SIP

guidance is written in such a way as to advance the state of the art of

VMT modeling in areas required to prepare SIPs or to require these

areas to address every identifiable shortcoming with their particular

modeling techniques. Regarding the commentor's assertions about VMT

growth since the SIP was submitted, the reader should refer to EPA's

response, above, regarding this issue.

5. The regional network. One commentor stated that the DRCOG

regional transportation network could not be properly used for SIP

purposes because of inaccurate assumptions made within the modeling

regarding whether certain projects would or would not be built.

The commentor specifically noted that the construction of the final

segment of E470 was not included in DRCOG's long-range transportation

modeling, ostensibly because funding was not available for that

project, while several light rail projects were included in the

modeling even though funding for those projects is not certain.

However, none of these projects were intended to be completed during

the timeframe of the SIP's attainment and maintenance demonstrations

(i.e., by the end of December 1998) and are not included in the SIP

modeling. Thus, EPA's approval of the SIP is not affected in any way by

the implementation or delay of these projects.

The commentor also states that its ALTLOP--alternative list of

projects--would have produced lesser growth in PM10 than DRCOG's

list of projects. EPA notes that it cannot substitute its judgement for

the State's or DRCOG's regarding which projects or controls to

implement as long as the Act's requirements are met. The SIP

demonstrates attainment and maintenance of the PM10 standard with

the mix of projects selected by DRCOG.

6. Monitoring and air sampling. A commentor indicated that further

information would be forthcoming relating to continuity of monitoring,

siting of monitors and whether tire wear particles are properly

accounted for. EPA did not receive any further information on this

subject and so has no basis upon which to respond. It should be noted

that Colorado's State-wide SIP, which includes the Denver monitoring

network, was reviewed and approved by EPA on September 23, 1993 (see 58

FR 49434) as meeting the requirements of 40 CFR Parts 53 and 58, and

the appendices to Part 50.

[[Page 18720]]

7. Conformity. One commentor makes comments under this heading that

go to the validity of the SIP. The commentor suggests that a value of

149.9 g/m3 is too close to the NAAQS of 150 g/

m3 to be considered attainment, particularly when the projections

used to effect this razor thin margin are acknowledged to have been

``low''. Regarding the 149.9 g/m3 value, EPA regulations

dictate that this value is considered attainment of the standard. See

40 CFR 50.6 and Part 50, Appendix K. By ``projections'', EPA assumes

the commentor is referring to the VMT projections relied on for the

attainment and maintenance demonstrations. As explained in response to

another comment, above, the difference between estimates of actual VMT

and projections of VMT contained in the SIP falls within a reasonable

margin of error and does not warrant a revision to or disapproval of

the SIP. The reader should refer to the comment and response, above,

for a more complete discussion of this issue.

The last sentence of the commentor's comment appears to relate to

the emissions budgets. EPA is not acting on the budgets in this action

and will defer its response until it acts on the budgets.

8. Other. One commentor endorsed EPA's proposed approval of the

Denver element of the PM10 SIP, citing air quality monitoring data

collected since 1992 that is below the current standard as evidence

that the plan is working. This comment requires no response.

III. This Action

EPA is approving the SIP revisions submitted by the Governor of

Colorado for the purpose of bringing about the attainment of the NAAQS

for PM10. The revisions were submitted to satisfy certain federal

requirements for moderate PM10 nonattainment areas. The bulk of

the revisions were adopted by the AQCC on October 20, 1994 with an

amendment on December 15, 1994 and were submitted by the Governor on

March 30, 1995. However, revisions to Regulation No. 13 (oxygenated

fuels) were adopted by the AQCC on October 19, 1995 and submitted to

EPA on December 22, 1995. EPA is basing its approval of the PM10

SIP on this October 19, 1995 version of Regulation No. 13 rather than

the version relied on in the March 30, 1995 submission. Also, the State

submitted a number of technical support documents to EPA after the

original June 7, 1993 PM10 SIP submittal that explain or are

relied on by the March 30, 1995 submittal and comprise part of the

basis for EPA's approval. These documents were submitted on June 8,

1993, June 10, 1993, June 25, 1993, July 19, 1993, August 5, 1993,

September 3, 1993, September 21, 1993, October 20, 1993, December 12,

1993, January 19, 1994, December 23, 1994, March 3, 1995, and November

8, 1995.

It should be noted that the March 30, 1995 submission, in addition

to including new control measures, also relies on control measures to

which EPA granted limited approval on July 25, 1994 (59 FR 37698). The

current action granting full approval to the PM10 SIP supersedes

EPA's limited approval. To avoid confusion, EPA is referencing in the

regulatory materials that are part of this document both new provisions

and provisions to which EPA gave limited approval in its July 25, 1994

action. These later provisions include portions of Regulation No. 1 and

Regulation No. 4 that, through administrative error, EPA inadvertently

failed to reference in the incorporation by reference section of the

July 1994 action. To correct this clerical error, EPA is now

incorporating all of Regulation No. 4, and all of Regulation No. 1

except Section V. As noted in EPA's action of December 3, 1986 (51 FR

43610), the sources subject to Section V of Regulation No. 1 are no

longer operating, and thus, there is no reason to act on Section V.

EPA is approving the control strategies that are relied upon in the

March 30, 1995 submission as well as the attainment and maintenance

demonstrations contained therein. EPA views the following measures as

reasonable, enforceable, and responsible for PM10 emissions

reductions in the Denver PM10 nonattainment area: (1) Colorado

Regulation No. 4 which regulates residential wood burning; (2) local

woodburning ordinances and resolutions; (3) Colorado Regulation No. 16

which establishes street sanding and sweeping requirements; (4) the

federal tailpipe standards, which provide an ongoing benefit due to

fleet turnover, and Colorado Regulations 11, 12, and 13 which were

developed by the State and approved by EPA independently from the

PM10 SIP but are included because of their particulate emission

reduction benefit; (5) Colorado Regulation No. 1, which provides

stationary source emission control regulations for particulates,

smokes, carbon monoxide and sulfur oxides 3; and (6) individual

stationary source permit revisions for Public Service Company Cherokee

facility, Purina Mills, Electron Corporation, TRIGEN--Colorado Energy

Corporation 4, Rocky Mountain Bottle Company, Conoco Refinery, and

Adolph Coors Brewery. The State's submission demonstrates attainment of

the PM10 NAAQS by December 31, 1994, with continued maintenance of

the standard through December 31, 1997.

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\3\ Carbon monoxide is not relevant to the PM10 SIP.

However, EPA is incorporating by reference Section IX of Regulation

No. 1 that relates to CO to accurately reflect the reorganization of

the regulation.

\4\ Permit changes for TRIGEN achieve PM10 SIP precursor

emission reductions to accommodate precursor emission increases at

the Rocky Mountain Bottle facility (formerly the Coors Glass Plant).

While these revisions to the emissions limits are acceptable for

meeting RACM/RACT requirements, EPA's action herein regarding these

limits does not in any manner relieve these companies of the

obligation to comply with any nonattainment NSR permitting

requirements that might apply to such changes in emissions limits.

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A more detailed discussion of the individual source contributions

and their associated control measures (including available control

technology) can be found in the Technical Support Document accompanying

EPA's October 3, 1996 proposed approval of the Denver moderate

PM10 nonattainment area SIP (61 FR 51631). As noted elsewhere in

this action, EPA received comments on the proposed action to approve

the Denver PM10 SIP. EPA believes that the responses set forth in

this action adequately address the comments and is proceeding with the

approval as proposed.

EPA has reviewed this request for revision of the federally-

approved SIP for conformance with the provisions of the Act. EPA has

determined that this action conforms to those requirements.

Nothing in this action should be construed as permitting or

allowing or establishing a precedent for any future request for

revision to any SIP. Each request for revision to any SIP shall be

considered separately in light of specific technical, economic, and

environmental factors and in relation to relevant statutory and

regulatory requirements.

IV. Executive Order (EO) 12866

This action has been classified as a Table 3 action 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.

V. Regulatory Flexibility

Under the Regulatory Flexibility Act, 5 U.S.C. 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. 603 and 604).

Alternatively, EPA may certify

[[Page 18721]]

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

jurisdiction 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 final 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).

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 today's final approval action does 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

requirements. Accordingly, no additional costs to State, local or

tribal governments, or to the private sector, result from these

actions.

VII. Submission to Congress and the General Accounting Office

Under 5 U.S.C. 801(a)(1)(A) as added by the Small Business

Regulatory Enforcement Fairness Act of 1996, EPA submitted a report

containing this rule and other required information to the U.S. Senate,

the U.S. House of Representatives and the Comptroller of the General

Accounting Office prior to publication of the rule in today's Federal

Register. This rule is not a ``major rule'' as defined by 5 U.S.C.

804(2).

VIII. Petitions for Judicial Review

Under section 307(b)(1) of the Act, petitions for judicial review

of this action must be filed in the United States Court of Appeals for

the appropriate circuit by June 16, 1997. Filing a petition for

reconsideration by the Administrator of this final rule does not affect

the finality of this rule for the purposes of judicial review nor does

it extend the time within which a petition for judicial review may be

filed, and shall not postpone the effectiveness of such rule or action.

This action may not be challenged later in proceedings to enforce its

requirements (see section 307(b)(2)).

List of Subjects in 40 CFR Part 52

Environmental protection, Air pollution control, Hydrocarbons,

Incorporation by reference, Intergovernmental relations, Nitrogen

dioxide, Particulate matter, Reporting and record keeping requirements,

Sulfur dioxide, and Volatile organic compounds.

Dated: February 28, 1997.

Jack W. McGraw,

Acting Regional Administrator.

Part 52, chapter I, title 40 of the Code of Federal Regulations is

amended as follows:

PART 52--[AMENDED]

1. The authority citation for part 52 continues to read as follows:

Authority: 42 U.S.C. 7401-7671q.

Subpart G--Colorado

2. Section 52.320 is amended by adding paragraph (c)(82) to read as

follows:

Sec. 52.320 Identification of plan.

* * * * *

(c) * * *

(82) The Governor of Colorado submitted the Denver moderate

nonattainment area PM10 State Implementation Plan (SIP) with a

letter dated March 30, 1995. The Governor submitted revisions to

Regulation No. 13, one of the control measures relied on in the

PM10 SIP, on December 22, 1995. These submittals as well as

support documentation submittals made on June 8, 1993, June 10, 1993,

June 25, 1993, July 19, 1993, August 5, 1993, September 3, 1993,

September 21, 1993, October 20, 1993, December 12, 1993, January 19,

1994, December 23, 1994, March 3, 1995, and November 8, 1995 satisfy

those moderate PM10 nonattainment area SIP requirements due for

the Denver PM10 nonattainment area on November 15, 1991. EPA is

approving the SIP. This approval replaces the previous limited approval

at 40 CFR 52.320(c)(61).

(i) Incorporation by reference.

(A) Regulation No. 4, ``Regulation on the Sale of New Woodstoves

and the Use of Certain Woodburning Appliances During High Pollution

Days,'' 5 CCR 1001-6, as adopted by the Air Quality Control Commission

on June 24, 1993, effective August 30, 1993.

(B) Local woodburning ordinances and resolutions.

(1) Arvada, Colorado. Ordinance number 2451, effective November 2,

1987, regarding woodburning restrictions.

(2) Aurora, Colorado. Ordinance numbers 87-118 and 92-14, effective

May 22, 1987 and May 22, 1992, respectively, regarding woodburning

restrictions.

(3) Boulder, Colorado. Ordinance numbers 5007 and 5445, adopted

November 25, 1986 and April 21, 1992, respectively, regarding

woodburning restrictions.

(4) Broomfield, Colorado. Ordinance number 794, effective November

24, 1988, regarding woodburning restrictions.

(5) Denver, Colorado. Ordinance numbers 293 and 1018, approved May

30, 1990 and December 16, 1993, respectively, regarding woodburning

restrictions.

(6) Douglas County, Colorado. Resolution number 991-128, adopted

November 14, 1991, regarding woodburning restrictions.

(7) Englewood, Colorado. Ordinance numbers 31 and 39, passed on

July 20, 1992, regarding woodburning restrictions.

(8) Federal Heights, Colorado. Ordinance number 565, adopted

January 5, 1988, regarding woodburning restrictions.

(9) Glendale, Colorado. Ordinance numbers 2 and 14, adopted January

5, 1988 and effective on October 20, 1992, respectively, regarding

woodburning restrictions.

(10) Greenwood Village, Colorado. Ordinance numbers 17 and 9,

effective July 9, 1988 and March 25, 1992, respectively, regarding

woodburning restrictions.

[[Page 18722]]

(11) Jefferson County, Colorado. Resolution numbers CC89-873 and

CC90-617, dated December 29, 1989 and August 7, 1990, respectively,

regarding woodburning restrictions.

(12) Lafayette, Colorado. Ordinance number 24; series 1988,

effective November 15, 1988, regarding woodburning prohibitions.

(13) Lakewood, Colorado. Ordinance numbers 0-86-113 and 0-92-61,

effective December 1, 1986 and November 28, 1992, respectively,

regarding woodburning restrictions.

(14) Littleton, Colorado. Ordinance numbers 51 and 26, passed on

December 6, 1988 and August 18, 1992, respectively, regarding

woodburning restrictions.

(15) Longmont, Colorado. Ordinance number 0-89-1, adopted December

27, 1988, regarding woodburning restrictions.

(16) Mountain View, Colorado. Ordinance number 90-5, approved on

January 7, 1991, regarding woodburning restrictions.

(17) Sheridan, Colorado. Ordinance numbers 22 and 1, approved

October 25, 1988 and February 9, 1993, respectively, regarding

woodburning restrictions.

(18) Thornton, Colorado. Ordinance numbers 2120 and 2194, adopted

October 28, 1991 and September 28, 1992, respectively, regarding

woodburning restrictions.

(19) Westminster, Colorado. Ordinance numbers 1742 and 2092,

enacted on November 9, 1987 and December 28, 1992, respectively,

regarding woodburning restrictions.

(C) Regulation No. 16, ``Concerning Material Specifications for,

Use of, and Clean-up of Street Sanding Material,'' 5 CCR 1001-18, as

adopted by the Air Quality Control Commission on September 22, 1994,

effective November 30, 1994.

(D) Regulation No. 1, ``Emission Control Regulations for

Particulates, Smokes, Carbon Monoxide, and Sulfur Oxides for the State

of Colorado,'' 5 CCR 1001-3, Sections I-IV and VI-IX, and Appendices A

and B, as adopted by the Air Quality Control Commission on August 19,

1993, effective October 20, 1993; with revisions to Sections VII and

VIII, adopted by the Air Quality Control Commission on September 22,

1994, effective November 30, 1994.

(E) Public Service Company Cherokee facility SO2 emission

limitations for the power facility.

(1) Permit 86AD352(1), effective date November 13, 1986, regulates

SO2 emissions at Unit #1.

(2) Permit 86AD352-2, effective date April 30, 1992, regulates

SO2 emissions at Unit #4.

(F) Purina Mills Inc. total PM10 emissions limitations at the

animal feed manufacturing facility.

(1) Permit 93AD1008-1, effective date October 19, 1993, regulating

emissions at the finished product loadout facility.

(2) Permit 93AD1008-2, effective date October 19, 1993, regulating

emissions at the grain receiving facility.

(G) Electron Corporation total PM10 emission limitations at

the gray iron foundry.

(1) Permit 93AR1363-1, effective date January 12, 1994, regulating

emissions at the Table shot blaster and associated baghouse.

(2) Permit 93AR1363-2, effective date January 12, 1994, regulating

emissions at the five grinding booths-stand and associated baghouse.

(3) Permit 93AR1363-3, effective date January 12, 1994, regulating

emissions at the five grinding booths-hand and associated baghouse.

(4) Permit 93AR1363-4, effective date January 12, 1994, regulating

emissions at the Muller-25 sand system and associated baghouse.

(5) Permit 93AR1363-5, effective date January 12, 1994, regulating

emissions at the Coleman core oven-sand.

(6) Permit 93AR1363-6, effective date January 12, 1994, regulating

emissions at the Spinner wheelabrator and associated baghouse.

(7) Permit 93AR1363-7, effective date January 12, 1994, regulating

emissions at the Sand sile-core room and associated baghouse.

(8) Permit 93AR1363-8, effective date January 12, 1994, regulating

emissions from pouring of molten iron (casting) and castings cooling.

(9) Permit 93AR1363-9 effective date January 12, 1994, regulating

emissions at three tumble blast machines and associated baghouse.

(10) Permit 93AR1363-10, effective date January 12, 1994,

regulating emissions at two mullers-80A and associated baghouse.

(11) Permit 93AR1363-11, effective date January 12, 1994,

regulating emissions at the Casting shakeout hood and associated

baghouse.

(12) Permit 93AR1363-12, effective date January 12, 1994,

regulating emissions at the Casting-disamatic mold and associated

baghouse.

(13) Permit 93AR1363-13, effective date January 12, 1994,

regulating emissions at the Sand silo-disamatic and associated

baghouse.

(14) Permit 93AR1363-14, effective date January 12, 1994,

regulating emissions at the Sand silo-air set room and associated

baghouse.

(15) Permit 93AR1363-15, effective date January 12, 1994,

regulating emissions at two electric induction furnaces and associated

baghouse.

(16) Permit 93AR1363-16, effective date January 12, 1994,

regulating emissions at two Inducto-Therm electric induction furnaces

model #2000/4, serial nos. 40102 and 40103, and associated baghouse.

(17) Permit 93AR1363-17, effective date January 12, 1994,

regulating emissions from chemicals used in core making process.

(18) Permit 93AR1363-18, effective date January 12, 1994,

regulating emissions at the Loop shakeout and associated baghouse.

(19) Permit 93AR1363-19, effective date January 12, 1994,

regulating emissions at the Floor shakeout and associated baghouse.

(20) Permit 93AR1363-20, effective date January 12, 1994,

regulating emissions at the Reclaim sand and associated baghouse.

(21) Permit 93AR1363-21 effective date January 12, 1994, regulating

emissions at the Sand heater/cooler and associated baghouse.

(22) Permit 93AR1363-22, effective date January 12, 1994,

regulating emissions at the Paint spray booth.

(H) TRIGEN-Colorado Energy Corporation permit emissions limitations

at two boilers.

(1) Permit 10JE660, effective date February 25, 1997, regulating

emissions at the #4 boiler: tangential fired cogeneration steam boiler.

(2) Permit 11JE305-1, effective date February 19, 1997, regulating

emissions at the #5 boiler: tangential fired cogeneration steam boiler.

(I) Rocky Mountain Bottle Company emission limitations on three

furnaces.

(1) Permit 92JE129-1, effective date June 29, 1995, regulating

emissions at the KTG glass melting furnaces #1, #2 and #3.

(J) Conoco Refinery allowable emission limitations from the

refinery.

(1) Permit 90AD524, effective date March 20, 1991, regulating a

Tulsa natural gas fired 20MMbtu/hour heater equipped with low-NOX

burners.

(2) Permit 90AD053, effective date March 20, 1991, regulating

process heaters H-10, H-11 and H-27 and process boilers B4, B6, and B8

all burning fuel gas only.

(3) Permit 91AD180-3, effective December 28, 1992, regulating the

three stage Claus sulfur recovery unit with tail gas recovery unit.

(ii) Additional material.

(A) Regional Air Quality Council, ``Guidelines for Reducing Air

Pollution from Street Sanding'' sets voluntary guidelines for public

works departments to follow to reduce the amount of street

[[Page 18723]]

sand applied, and includes recommendations for increasing the

effectiveness of street cleaning operations.

3. Section 52.332 is amended by adding paragraph (f) to read as

follows:

Sec. 52.332 Moderate PM10 Nonattainment Area Plans.

* * * * *

(f) On March 30, 1995, and November 17, 1995, the Governor of

Colorado submitted the moderate PM10 nonattainment area plan for

the Denver area. The March 30, 1995 submittal was made to satisfy those

moderate PM10 nonattainment area SIP requirements due for the

Denver PM10 nonattainment area on November 15, 1991. The November

17, 1995 submittal was also made to satisfy the PM10 contingency

measure requirements which were due for Denver on November 15, 1993.

[FR Doc. 97-9948 Filed 4-16-97; 8:45 am]

BILLING CODE 6560-50-P