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Proposed Rule

Approval and Promulgation of Air Quality Implementation Plans; State of Utah; Utah County PM10

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AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Proposed rule.

SUMMARY:

On July 3, 2002, the Governor of Utah submitted a State Implementation Plan (SIP) revision for the Utah County nonattainment area for particulates of 10 microns in size or smaller (PM10). The Utah Department of Air Quality's (UDAQ) submittal, among other things, revises the existing attainment demonstration in the approved PM10 SIP based on a short-term emissions inventory, establishes 24-hour emission limits for the major stationary sources in the Utah County PM10 nonattainment area and establishes motor vehicle emission budgets based on EPA's most recent mobile source emissions model, Mobile6. In this action, EPA is proposing approval and soliciting public comment on the SIP revision. This action is being taken under sections 107, 110, and 189 of the Clean Air Act (Act).

DATES:

Written comments must be received on or before October 10, 2002.

ADDRESSES:

Written comments may be mailed to Richard R. Long, Director, Air and Radiation Program, Mailcode 8P-AR, Environmental Protection Agency (EPA), Region VIII, 999 18th Street, Suite 300, Denver, Colorado, 80202-2466. Copies of the documents relevant to this action are available for public inspection during normal business hours at the Air and Radiation Program, Environmental Protection Agency, Region VIII, 999 18th Street, Suite 300, Denver, Colorado, 80202-2466. Copies of the State documents relevant to this action are available for public inspection at the Utah Department of Environmental Quality, Division of Air Quality, 150 North 1950 West, Salt Lake City, Utah 84114-4820.

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FOR FURTHER INFORMATION CONTACT:

Libby Faulk, EPA, Region VIII, (303) 312-6083.

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SUPPLEMENTARY INFORMATION:

Throughout this document, wherever “we”, “us”, or “our” are used, we mean the Environmental Protection Agency (EPA).

Table of Contents

I. EPA's Proposed Action

A. What Action Is EPA Proposing To Take?

II. Summary of SIP Revision

A. Did Utah Follow the Proper Procedures for Adopting this Action?

B. What Changes to the SIP Is EPA Proposing to Approve?

1. Transportation Conformity Requirements

2. Updated Emissions Inventory and Attainment Demonstration

3. Establishment of Enforceable Short-Term Emission Limits for Major Stationary Sources

4. Director's Discretion Provisions

III. UDAQ's Commitment for Future SIP Revisions

IV. Background

IV. Administrative Requirements

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I. EPA's Proposed Action

A. What Action Is EPA Proposing To Take?

We are proposing to approve the Governor of Utah's submittal of July 3, 2002, that requests our approval of the Utah County PM10 SIP revision that Utah adopted on June 5, 2002 and July 3, 2002.[1] With the SIP revision, Utah has revised Section IX (Section 9 under our current approved version of the Utah SIP), “Control Measures for Area and Point Sources,” Part A, “Fine Particulate Matter” and Part H, “Emission Limits.” In addition, Utah revised its regulation R307-110-10 (R307-2-10 under our current approved version of the Utah SIP) to incorporate by reference its July 3, 2002 revision of the Utah County portion of the Utah SIP, Section IX, Part A. In addition, Utah revised its regulation R307-110-117 (R307-2-17 under our current approved version of the Utah SIP) to incorporate by reference its June 5, 2002 revision of the Utah County portion of the Utah SIP, Section IX, Part H. We are soliciting public comment on all aspects of this proposed SIP rulemaking action. Any comments received by the deadline stated in the Dates section of this document will be considered before taking final action. Interested parties may participate in the Federal rulemaking procedure by submitting written comments to the EPA Regional office listed in the ADDRESSES section of this document.

II. Summary of SIP Revision

A. Did Utah Follow the Proper Procedures for Adopting This Action?

Section 110(k) of the CAA addresses our actions on submissions of revisions to a SIP. The Act also requires States to observe certain procedural requirements in developing implementation plans and plan revisions for submission. 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. 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.

We also must determine whether a submittal is complete and therefore warrants further review and action [see section 110(k)(1) and 57 FR 13565, April 16, 1992]. Our completeness criteria for SIP submittals are set out at 40 CFR part 51, appendix V. We attempt to make completeness determinations within 60 days of receiving a submission. However, a submittal is deemed complete by operation of law under section 110(k)(1)(B) if a completeness determination is not made within six months after receipt of the submission.

On March 13, 2002 the Utah Air Quality Board agreed to propose the Utah County PM10 SIP revision for public comment. Copies of the proposed changes were made available to the public and the Air Quality Board held public hearings on April 23, 2002 and April 24, 2002 to consider public comment on the above SIP revision. Utah addressed comments received before the final adoption of the revision. The Utah County SIP revision was subsequently adopted by the Utah Air Quality Board on June 5 and July 3, 2002. The revision was formally submitted to us for approval with a Governor's letter dated July 3, 2002. Utah's SIP revision will be state-effective on September 1, 2002. We reviewed these SIP materials for conformance with the completeness criteria in 40 CFR part 51, appendix V and determined that Utah's submittal was administratively and technically complete for purposes of parallel processing. Pursuant to section 110(k)(1)(B), we informed Utah of our completeness determination with a August 15, 2002 letter from Robert E. Roberts, Regional Administrator to Governor Michael Levitt.

B. What Changes to the SIP Is EPA Proposing To Approve?

1. Transportation Conformity Requirements

This SIP revision establishes motor vehicle emission budgets and includes an analysis of those budgets. Under EPA's regulations at 40 CFR part 93, the Metropolitan Planning Organization (MPO) is required to determine conformity of transportation plans and projects to the motor vehicle emission budgets as approved in the PM10 SIP. The MPO in Utah County is the Mountainland Association of Governments (MAG).

Utah County has been in a conformity lapse since August 2000 because transportation plans for the area could not meet the PM10 and NOX motor vehicle emission budgets that were derived from the emissions inventory in the approved PM10 SIP.[2] Utah County could not meet the established motor vehicle emission budgets because the budgets were based on an outdated mobile source emissions model (Mobile 4) [3] and the area exceeded its growth projections.

This SIP revision establishes new motor vehicle emission budgets for PM10 and NOX which are based on the latest planning assumptions, including the latest growth projections, and the latest emissions model (Mobile 6), released on January 29, 2002 (67 FR 4254). The new motor vehicle emission budgets are established for years 2003, 2010, and 2020 and take into account growth in all other source categories. Please refer to Table 1: Transportation Conformity Motor Vehicle Emission Budgets.

Table I.—Transportation Conformity Motor Vehicle Emission Budgets

YearPrimary PM (tons/day)NOX (tons/day)
20036.5720.35
20107.7412.75
202010.345.12

The values for 2003 reflect the inventory values for motor vehicles that were used in the CMB modeling. The CMB modeling, based on these inventory values, and inventory values for other source categories, demonstrates attainment in 2003. For 2010 and 2020, inventory values for all source categories were projected forward. The 2010 and 2020 motor vehicle emissions budgets reflect the motor vehicle inventory values in 2010 and 2020, except that “road dust” and “brake wear” portions of the 2020 motor vehicle inventory for PM10 were expanded by 7 percent to take advantage of part of the available safety margin in that year. Per 40 CFR 93.101, the safety margin is the amount by which the total projected emissions from all sources of a given pollutant are less than the total emissions that would satisfy the applicable requirement for reasonable further progress, attainment or maintenance. The applicable standard for PM10 is 150 μg/m;3 even using the expanded 2020 motor vehicle emissions budget for PM10 reflected in the table above, the CMB projections for 2020 Start Printed Page 57359show a maximum concentration of 146.4 μg/m3, still below the 150 μg/m3 standard.

If we approve them, the emissions budgets must be used for conformity determinations per 40 CFR 93.118. Specifically, the 2003 budgets will apply for years 2003 through 2009, the 2010 budgets will apply for years 2010 through 2019, and the 2020 budgets will apply for years 2020 and beyond. In addition, after our final approval of the motor vehicle emission budgets and upon the Federal Highway Administration's approval of a positive conformity determination, the present conformity lapse in Utah County will end.

On March 2, 1999, the United States Court of Appeals for the District of Columbia Circuit issued a decision in Environmental Defense Fund vs. the Environmental Protection Agency, No. 97-1637, that we must make an affirmative determination that the submitted motor vehicle emission budgets contained in SIPs are adequate before they are used to determine the conformity of Transportation Improvement Programs or Long Range Transportation Plans. In response to the court decision, we are making most submitted SIP revisions containing a control strategy plan available for public comment and responding to these comments before announcing our adequacy determination. (We do not perform adequacy determinations for SIP revisions that only create new emission budgets for years in which an EPA-approved SIP already establishes a budget, because these new budgets cannot be used for conformity until they are approved by EPA.) We make the motor vehicle emission budgets in SIP revisions available for comment by posting notification of their availability on our Web site (currently, these notifications are posted at www.epa.gov/​oms/​transp/​conform/​adequacy.htm). The adequacy process is discussed in greater detail in a May 14, 1999 memorandum from Gay MacGregor entitled “Conformity Guidance on Implementation of March 2, 1999 Conformity Court Decision,” also available on our Web site at: http://www.epa.gov/​oms/​transp/​traqconf.htm.

Because they extend beyond the time-frame of the previously approved Utah County PM10 SIP, we are reviewing the 2010 and 2020 motor vehicle emission budgets in this plan for adequacy using the criteria located at 40 CFR 93.118(e). The 2003 motor vehicle emission budgets would replace the previously approved 2003 budgets in the Utah County PM10 SIP revision and can't be used for purposes of demonstrating conformity unless and until we finally approve the Utah County PM10 SIP revision. The 2010 and 2020 motor vehicle emission budgets have been posted to our Web site at: http://www.epa.gov/​oms/​transp/​conform/​adequacy.htm and are available for public comment. If and when the 2010 and 2020 motor vehicle emission budgets are found to be adequate, the Utah Department of Transportation and the Federal Highway Administration must use these budgets in future conformity analyses, even if we do not publish a final rule approving the Utah County PM10 SIP revision.

2. Updated Emissions Inventory and Attainment Demonstration

The emissions inventory for the Utah County PM10 nonattainment area covers emissions from all sources of both primary and secondary PM10 inside Provo and Orem. The SIP revision uses a 1988 and 1989 base year emissions inventory, as well as a 2003 projected emissions inventory for all sources in the inventory domain. The 1988/89 base year inventory was updated for purposes of this SIP revision to create a 24-hour inventory in order to be protective of the 24-hour PM10 National Ambient Air Quality Standards (NAAQS). The 1994 approved version of the PM10 SIP includes an emissions inventory based on monthly and annual PM10 values. The 2003 projected emissions inventory, which also contains 24-hour values, has been updated to reflect stationary source shut-downs and other changes affecting PM10, NOX, and SO2 emissions that have occurred since the development of the original PM10 SIP. The mobile source portion of both the base year and projected inventories were updated to include the use of the new Mobile6 emissions model.

Utah updated the existing attainment demonstration from the original PM10 SIP to again create an analysis based on 24-hour averages instead of annual values. Utah used the existing chemical mass balance (CMB) methodology for the 24-hour attainment demonstration. The CMB analysis was also updated to account for changes that have occurred since the development of the original PM10 SIP. One such change to the attainment demonstration is that Utah increased the wood burning control strategy effectiveness to 90%, meaning that additional reductions in woodburning emissions are calculated into the attainment demonstration. In addition, since the development of the original PM10 SIP, some sources in the Utah County nonattainment area have banked emissions. Although these emissions are banked, the potential exists for the purchase and use of part or all of such banked emissions. Because of this, Utah has accounted for these banked emissions in the attainment demonstration by assessing the emissions to the source from which they came.

Utah's revised attainment demonstration for Utah County projects attainment for 2002 and 2003 for SIP purposes, and for 2010 and 2020 for conformity purposes only. In this revised SIP, the CMB analysis is based on 1988 and 1989 recorded monitoring data, which is the same data used in the original SIP. Table II below shows the results of the CMB analysis on the projected attainment years using only the highest concentration site for each year. Please refer to the Utah County SIP revision and technical support document (TSD) for more detailed information. Utah used three monitoring sites to demonstrate attainment on numerous high concentration days, although a demonstration of attainment is only required for the design day. In the table below, we only present results from the established design day (this is the same design day as in the original SIP revision).

Table II.—Utah County PM10 CMB Analysis Results in μg/m3 at Highest Concentration Monitor

Sources2002 (Lindon)2003 (Lindon)2010 (North Provo)
Geneva Steel51.551.538.7
Point Sources 423.523.518.5
Mobile Sources46.545.856.1
Area Sources17.417.716.8
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Total Concentration138.9138.4130.0
4 All point sources in Provo and Orem, excluding Geneva Steel. Includes secondary sulfates and nitrates.

In the original SIP as well as in this SIP revision, Utah uses three monitoring sites to demonstrate attainment: Lindon, North Provo and West Orem. The West Orem monitoring site has been shut down since December 31, 1997.

3. Establishment of Enforceable Short-Term Emission Limits for Major Stationary Sources

The original Utah County PM10 SIP includes the entire permit (circa 1988-1991) for most of the stationary sources in Provo and Orem. We only require that the major stationary sources of PM10 and its precursors have specific limits in SIPs. For these majors sources, it is important to include their appropriate emission limits and the enforceable provisions for those limits, but it's usually not essential to include their entire permit. Because Utah County is designated nonattainment for the 24-hour PM10 NAAQS, the SIP limits must include short-term limits with an averaging time of 24 hours or less. To determine which sources should be treated as major sources for purposes of the PM10 SIP, threshold limits were chosen of 100 tons per year of primary PM10 emissions, 200 tons per year of NOX emissions, and 250 tons per year of SO2 emissions. UDAQ's and EPA's analysis of the sources in Provo and Orem showed that sources above these levels account for a high percentage of stationary source emissions in the area. The five sources with explicit emission limits in the Utah County PM10 SIP revision are, Geneva Steel, Geneva Nitrogen, Inc., Provo City Power, Springville City Corporation and Geneva Rock Product's Asphalt Plant Baghouse Stack. Table III below shows the emission limits established through this SIP revision for the major sources, except Geneva Steel.

Table III.—Emission Limits for Stationary Sources in Tons/Day

SourcesPrimary PM10NOXSO2
Geneva Nitrogen, Inc.—Montecantini Acid Plant Vent0.389
Geneva Nitrogen, Inc.—Weatherly Acid Plant Vent0.233
Geneva Nitrogen, Inc.—Prill Tower0.24
Geneva Rock Products Asphalt Plant Baghouse Stack0.1030.5680.484
Provo City Power2.45
Springville City Corporation1.68

Table IV below provides the proposed 24-hour emission limits for the major emitting units at Geneva Steel for September through May, and Table V below provides the proposed 24-hour emission limits for the major emitting units at Geneva Steel for June through August. Table VI below provides the proposed annual emission limits for Geneva Steel's major emitting units.

Table IV.—Emission Limits for Geneva Steel in Tons/Day (September-May)

Geneva steel sourcePrimary PM10NOXSO2
Coke Plant 50.10.0
Sinter Plant 6
Blast Furnace1.3
Q-BOP0.5
Geneva Other 71.2
Secondary Sulfate1.0
Secondary Nitrate7.7
5 All NOX emissions from coke plant ovens have been banked. Emissions of NOX associated with continuing operations in the vicinity of the coke plant (coke pile handling) are accounted for in the secondary nitrate limit.
6 All emissions of PM10, SO2, and NOX from the sinter plant have been banked.
7 The “Geneva Other” category includes the power house, rolling mill and fugitive emissions.

Table V.—Emission Limits for Geneva Steel in Tons/Day (June-August)

Geneva steel sourcePrimary PM10NOXSO2
Coke Plant 80.10.0
Sinter Plant 9
Blast Furnace1.3
Q-BOP0.5
Geneva Other1.4
Secondary Sulfate3.4
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Secondary Nitrate9.6
8 All NOX emissions from coke plant ovens have been banked. Emissions of NOX associated with continuing operations in the vicinity of the coke plant (coke pile handling) are accounted for in the secondary nitrate limit.
9 All emissions of PM10, SO2, and NOX from the sinter plant have been banked.

Table VI.—Annual Emission Limits for Geneva Steel in Tons/Year

Geneva steel sourcePrimary PM10NOXSO2
Coke Plant 829.60.0
Sinter Plant 9
Blast Furnace454.4
Q-BOP178.2
Geneva Other448.1
Secondary Sulfate560.2
Secondary Nitrate2971.8
8 All NOX emissions from coke plant ovens have been banked. Emissions of NOX associated with continuing operations in the vicinity of the coke plant (coke pile handling) are accounted for in the secondary nitrate limit.
9 All emissions of PM10, SO2, and NOX from the sinter plant have been banked.

It is important to note here that Geneva Steel is in the process of banking a significant amount of its emissions from the coke plant, sinter plant, Q-BOP, and sources in the “Geneva Other” category. This is due to the shutting down or reduction in emissions for the coke plant (some fugitive emissions remain from the coke piles), sinter plant, foundry and rolling mill scarfer facility. Emissions reductions are also due to fuel switching. Table VII below shows the banked emissions per process in tons per year of PM10, NOX, and SO2. Where Tables IV, V and VI reflect that all process emissions have been banked, no emissions from such process will occur under the SIP revision.

Table VII.—Banked Emissions for Geneva Steel in Tons/Year

Geneva steel sourcePrimary PM10NOXSO2
Coke Plant461.8557.2454.9
Sinter Plant101.0705.2434.2
Q-BOP27.2
Geneva Other51.0
Total6411262.4889.1

4. Director's Discretion Provisions

The EPA-approved PM10 SIPs for Utah County and Salt Lake County contain provisions that some would argue allow the Executive Secretary of the State of Utah to make changes effective to the SIP without first obtaining EPA approval. We believe these “director's discretion” provisions are contrary to the CAA and should not have been approved into the SIP.

At the very least, these provisions have led to uncertainty regarding the content of the federally enforceable SIP. In order to address these concerns, Utah has inserted the following language into the SIP: “Notwithstanding any other provision in the Utah SIP, no change to this SIP revision shall be effective to change the federal enforceability of the emission limits or other requirements of the Utah County PM10 SIP without EPA approval of such change as a SIP revision.” This language makes clear that Utah may not unilaterally change the limits and requirements of the federally enforceable SIP, and that Utah's changes to elements of the SIP will not be federally effective without EPA's approval. As explained further below, Utah has also committed to work with us in order to permanently resolve the director's discretion issues in the Salt Lake County and Utah County PM10 SIPs.

III. UDAQ's Commitment for Future SIP Revisions

With an April 18, 2002 letter from Richard Sprott, Director of Utah's Division of Air Quality to Richard Long, Director of the Air and Radiation Program in EPA Region 8, UDAQ committed to work with us to address remaining issues with the PM10 SIPs for both the Utah and Salt Lake County nonattainment areas and with the Utah SIP generally. Utah will address these ongoing issues in a SIP revision (which may be in the form of a maintenance plan) that will be submitted by March 1, 2004. Utah has committed to address the following issues with the existing SIP:

(1) State authority as it relates to the discretion granted to the Executive Secretary of the Utah Air Quality Board (EPA uses the term “director's discretion” for these provisions);

(2) Variance provisions as provided in Utah law, Air Quality regulations and the SIP;

(3) UAM-AERO based modeling and analysis to address pollutants of concern in the SIP or maintenance plan;

(4) Stationary source modeling for major sources and appropriate non-major sources to determine predicted impacts of emission limits established in the SIP or maintenance plan;

(5) Enforceable emission limits for sources in the SIP or maintenance plan, including enforceable 24-hour emission limits for major sources in both Salt Lake and Utah Counties and emission Start Printed Page 57362limits (or surrogates for emission limits) for refinery process flaring and SRU maintenance downtime;

(6) Emissions inventory and modeling analysis for the nonattainment areas in Salt Lake and Utah Counties;

(7) New source review, emissions banking, and interpollutant trading (EPA's issues with these programs were explained in a May 10, 2001 letter from Region 8 to UDAQ);

(8) Unavoidable breakdown rules and consistency with the EPA September 20, 1999 policy regarding such breakdowns;

(9) Inclusion of annual growth rates in the SIP or maintenance plans;

(10) Justification for credits and growth rates for wood and coal burning in Utah County;

(11) Backhalf emissions measuring for PM10 emissions limit stack testing;

(12) General language clean up in the PM10 SIP to assure SIP is consistent and reads appropriately;

(13) Diesel I/M revision or program withdrawal;

(14) Emission budgets for PM10 and NOX in Salt Lake portion of PM10 SIP;

(15) Emission inventory and modeling analysis for automobile emission inspection and maintenance program changes, if any such changes are made in the SIP or maintenance plan.

The above issues aren't addressed in this SIP revision for Utah County and therefore, these issues will continue after our potential final approval of this SIP revision.

IV. Background

On July 18, 1997, we promulgated new NAAQS for PM10 and PM2.5. However, on May 18, 1999, the United States Court of Appeals for the D.C. Circuit in American Trucking Associations, Inc. et al., v. United States Environmental Protection Agency vacated the 1997 PM10 standard. Because of the Court ruling, we are continuing to implement the pre-existing PM10 standard, and are therefore taking actions on SIP revisions for PM10 nonattainment areas.

The original Utah County and Salt Lake County nonattainment area PM10 SIPs were approved on July 8, 1994 (59 FR 35036).

IV. Administrative Requirements

Under Executive Order 12866 (58 FR 51735, October 4, 1993), this proposed action is not a “significant regulatory action” and therefore is not subject to review by the Office of Management and Budget. For this reason, this action is also not subject to Executive Order 13211, “Actions Concerning Regulations That Significantly Affect Energy Supply, Distribution, or Use” (66 FR 28355, May 22, 2001). This proposed action merely proposes to approve state law as meeting Federal requirements and imposes no additional requirements beyond those imposed by state law. Accordingly, the Administrator certifies that this proposed rule will not have a significant economic impact on a substantial number of small entities under the Regulatory Flexibility Act (5 U.S.C. 601 et seq.). Because this rule proposes to approve pre-existing requirements under state law and does not impose any additional enforceable duty beyond that required by state law, it does not contain any unfunded mandate or significantly or uniquely affect small governments, as described in the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4).

This proposed rule also does not have tribal implications because it will not have a substantial direct effect on one or more Indian tribes, on the relationship between the Federal Government and Indian tribes, or on the distribution of power and responsibilities between the Federal Government and Indian tribes, as specified by Executive Order 13175 (65 FR 67249, November 9, 2000). This action also does not have Federalism implications because it does not have substantial direct effects on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government, as specified in Executive Order 13132 (64 FR 43255, August 10, 1999). This action merely proposes to approve a state rule implementing a Federal standard, and does not alter the relationship or the distribution of power and responsibilities established in the Clean Air Act. This proposed rule also is not subject to Executive Order 13045 “Protection of Children from Environmental Health Risks and Safety Risks” (62 FR 19885, April 23, 1997), because it is not economically significant.

In reviewing SIP submissions, EPA's role is to approve state choices, provided that they meet the criteria of the Clean Air Act. In this context, in the absence of a prior existing requirement for the State to use voluntary consensus standards (VCS), EPA has no authority to disapprove a SIP submission for failure to use VCS. It would thus be inconsistent with applicable law for EPA, when it reviews a SIP submission, to use VCS in place of a SIP submission that otherwise satisfies the provisions of the Clean Air Act. Thus, the requirements of section 12(d) of the National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 note) do not apply. This proposed rule does not impose an information collection burden under the provisions of the Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.).

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List of Subjects in 40 CFR Part 52

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Dated: August 27, 2002.

Jack W. McGraw,

Acting Regional Administrator, Region VIII.

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Footnotes

1.  Although Utah adopted the SIP revision on June 5 and July 3, 2002, the revision will not be State-effective until September 1, 2002. We will not take final action on the SIP revision until after it has become effective. Because the Governor submitted the SIP revision to us for approval before its effective date, our proposal may be viewed as a limited use of our parallel processing procedures under 40 CFR part 51, appendix V.

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2.  EPA approved the PM10 SIP on July 8, 1994 (59 FR 35036).

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3.  Sections 40 CFR 93.110 and 93.111 require areas to use the latest planning assumptions and the latest emissions model for conformity determinations.

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[FR Doc. 02-22986 Filed 9-9-02; 8:45 am]

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