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Texas, El Paso Area, Ozone, Attainment Plan Summary

Texas, El Paso Area, Ozone Attainment Plan Summary

Federal Register Dates:
     Proposed Rule:  June 10, 2004 (69 FR 32475).
     Direct Final Rule:  June 10, 2004 (69 FR 32450-32454).
     Effective Date:  August 8, 2004

Area Covered: El Paso Ozone Nonattainment Area which consist of El Paso  County in Texas.

Type of Pollutant: Ozone (O3)

Below is relevant information copied from the direct final approval Federal Register action.
See 69 FR 32450 (June 10, 2004) for the complete Federal Register.

TITLE:  Approval and Promulgation of Implementation Plans for Texas; Approval
of Section 179B Demonstration of Attainment, Volatile Organic Compounds and
Nitrogen Oxides Motor Vehicle Emissions Budgets for Conformity for the El Paso
Ozone Nonattainment Area.  

ACTION: Direct final approval.

SUMMARY: The EPA is approving, through direct final action, a revision
to the Texas State Implementation Plan (SIP), submitted to show
attainment of the one-hour ozone National Ambient Air Quality Standard
(NAAQS) in the El Paso ozone nonattainment area, but for emissions
emanating from outside of the United States. The EPA is also approving
the El Paso area's Volatile Organic Compounds (VOCs) and Nitrogen
Oxides (NOX) emissions budgets. The State submitted the
revisions to satisfy sections 179B and other Part D requirements of the
Federal Clean Air Act (CAA).

SUPPLEMENTARY INFORMATION: Throughout this document "we," "us," and
``our'' means EPA.


I. What is the background for this action?
II. What did the state submit and how did we evaluate it?
    A. Modeling.
    B. Additional basin-wide modeling.
    C. How close is El Paso to attainment of the ozone standard?
    D. Motor vehicle emissions budget.
    E. Has the EPA approved other parts of the SIP before now?
III. What is our final action?
IV. Why is this a ``final action?''
V. Statutory and Executive Order Reviews.

I. What Is the Background for This Action?

    El Paso, Texas, was designated nonattainment for ozone and
classified as serious under sections 107(d)(4)(A) and 181(a) of the
CAA. The El Paso nonattainment area consists of El Paso County. Under
section 181(a), serious areas must attain the ozone NAAQS by November
15, 1999.
    The CAA requires that ozone nonattainment areas designated moderate
and above demonstrate attainment through air quality modeling or any
other analytical method determined by the Administrator to be at least
as effective. Section 179B of the CAA contains special provisions for
nonattainment areas that are affected by emissions emanating from
outside the United States. Under section 179B, the EPA will approve a
SIP if the area meets all other CAA requirements, and establishes that
implementation of the plan would achieve attainment of the ozone
standard by the CAA statutory deadline ``but for emissions emanating
from outside the United States.'' This is the type of demonstration
made by the State of Texas.

II. What Did the State Submit and How Did We Evaluate It?

A. Modeling

    The Governor of the State of Texas submitted a revision to the
Texas SIP for the El Paso ozone nonattainment area via a letter dated
October 3, 1994. This included air quality modeling, under section 179B
of the CAA, that demonstrates that El Paso would attain the ozone
NAAQS, but for emissions emanating from outside of the United States.
The State of Texas submitted a revision via a letter dated August 9,
1996, showing that the revised inspection and maintenance program, and
delay in implementation, would have no significant effect on the
validity of the attainment demonstration submitted in 1994.
    El Paso and Juarez, Mexico, share a common airshed. However,
emission inventory data was not available for Juarez, so modeling of
the entire airshed was not possible. In such an instance, section 179B
allows an area such as El Paso to perform modeling using only U.S.
pollutant emission data in performing the attainment demonstration.
    In its demonstration, the Texas Commission on Environmental Quality
(TCEQ) used the Urban Airshed Model (UAM) version IV, an EPA-approved
photochemical grid model, to develop the attainment demonstration for
the El Paso area. Texas performed its ozone modeling analyses for El
Paso, according to EPA guidance. For further details, see the Technical
Support Document.
    The State had previously submitted to the EPA the 15 percent VOC
Reasonable Further Progress (RFP) SIP for the El Paso area (63 FR
62943, November 10, 1998), as required by section 182(b)(1) of the CAA.
The 15 percent RFP SIPs contain regulations that are estimated to
reduce VOC emissions in each area by 15 percent from 1990 baseline
levels. The modeling results indicate that with the 15 percent RFP
reductions, the area would attain the 1-hour ozone standard, but for
emissions emanating from outside the United States, by November 15,
1996, which is before the area's applicable attainment deadline of
November 15, 1999. The predicted domain-wide maximum ozone
concentration for 1996 was significantly below the NAAQS of 120 ppb.

B. Additional Basin-Wide Modeling

    Section 182(c)(2) of the CAA requires each serious and above ozone
nonattainment area to submit a SIP revision by November 15, 1994, which
describes, in part, how the area will achieve an actual VOC emission
reduction from the baseline emissions of at least 3 percent of baseline
emissions per year averaged over each consecutive 3-year period
beginning 6 years after enactment (i.e., November 15, 1996), until the
area's attainment date.
    Via a letter from A. Stanley Meiburg of EPA Region 6 to Ms. Beverly
Hartsock of the then Texas Natural Resource Conservation Commission,
dated August 9, 1994, EPA stated its position that if the section 179B
attainment demonstration SIP showed the El Paso area would attain by
November 15, 1996, the attainment deadline for moderate areas, the
additional 9 percent in emission reductions required in the post-96
Rate of Progress (ROP) would be deferred. This deferral was effective
until Juarez monitoring data and emission inventory data became
available to perform basin-wide modeling of the El Paso/Jurez airshed.
    Annex V of the 1983 La Paz Agreement between the United States and
Mexico, which addressed environmental concerns along the border, calls
for basin-wide modeling to be accomplished for the El Paso/Juarez
airshed. This modeling was performed during the 1998-2000 period, but
was not deemed to be valid to ascertain the types of controls necessary
throughout the airshed in order to meet ozone air quality standards on
both the U.S. and the Mexico side of the border. The main problem with
model performance was believed to be an inadequate VOC emission
inventory for Juarez.
    However, subsequent to the submission of this attainment
demonstration, the El Paso area has now attained the 1-hour ozone
standard by the accumulation of three consecutive years of quality-
assured ambient air data that show no violations of the standard. The
most recent data provided by the State of Texas, available through the
EPA Aerometric Information and Retrieval Service, demonstrate the area
continues to attain the 1-hour standard. Therefore, EPA does not
anticipate a need to trigger the commitment for basin-wide modeling.
    Based on EPA's ``Clean Data Policy'', if EPA made an attainment
finding, we would no longer require the 9 percent ROP plan. Therefore,
since the El Paso area has data showing attainment of the ozone
standard without the 9 percent ROP plan, we believe that it is
reasonable to defer that ROP requirement. Complete details of EPA's
rationale are included in the Clean Data Policy. If the area violates
the 1-hour ozone standard before a future redesignation, EPA will
review the conclusion to defer the 9 percent ROP requirement.

C. How Close Is El Paso to Attainment of the Ozone Standard?

    Data from the El Paso monitoring network from 1999 to the end of
2002 indicate that the area is in attainment of the ozone standard. The
State has informed EPA that it may request redesignation in the near

D. Motor Vehicle Emissions Budget

    The Governor of Texas submitted the 1996 motor vehicle emissions
budgets of 36.23 tons/day for VOCs and 39.76 tons/day for
NOX on December 11, 1997. These budgets were found to be
adequate for transportation conformity purposes on January 12, 1998
(see 64 FR 31217, June 10, 1999). It is EPA's conclusion that the SIP
demonstrates attainment with these budgets and contains the measures
necessary to support them. Today, we are approving these budgets, under
section 176(c) of the CAA.

E. Has the EPA Approved Other Parts of the SIP Before Now?

    Below is a table describing the elements that the El Paso ozone SIP
must have, and the references to their EPA approvals.

                                                     Codified at 40 CFR
          Description             Section of CAA    part 52, subpart SS
An inventory of all actual      172(c)(3) and      52.2309(a).
 emissions of VOC and NOX        182(a)(1).
 sources in the area.
A revised inventory every       182(a)(3)(A).....  Most recent submitted
 three years.                                       1996.
A permit program for the        172(c)(5) and      52.2270(c)(88).
 construction and operation of   182(a)(2)(C);
 new and modified major          182(c)(6);
 stationary sources of VOC and   182(c)(7);
 NOX ozone in nonattainment      182(c)(8).
A regulation that requires      182(a)(3)(B).....  52.2270(c)(88).
 sources to legally certify
 their emissions each year.
A regulation requiring          182(c)(10).......  52.2270(c)(97).
 reductions in current
 emissions to offset new
 emissions from new and
 modified sources.
Reasonably available control    182(b)(2)........  52.2270(c)(88).
 technology on major sources
 of VOC's.
A fuels program to reduce       211(h)...........  52.2270(c)(88).
 evaporative emissions from
 vehicle fuel tanks.
Contingency measures to be      182(c)(9);         63 FR 62943, Nov. 10,
 implemented if the area fails   172(c)(9).         1998.
 to attain the standard by the
A vehicle inspection and        182(c)(3)........  52.2270(c)(87).
 maintenance program.
Vapor recovery systems on fuel  182(b)(3)........  52.2270(c)(81).
A clean fuel fleet program....  182(c)(4)........  52.2270(c).
Enhanced monitoring of ozone,   182(c)(1)........  52.2270(c)(90).
 NOX, VOC's, and NOX and VOC
Transportation control          182(c)(5)........  52.2308(b) (waiver of
 measures.                                          NOX provisions, and
                                                    63 FR 62943, Nov.
                                                    10, 1998).
A SIP revision to achieve 15    182(b)(1)........  63 FR 62943, Nov. 10,
 percent reductions in overall                      1998.
 VOC emissions.
A SIP revision to achieve 3     182(c)(2)(B).....  Deferred, based on
 percent reductions per year                        EPA's Clean Data
 in 1997, 1998, and 1999 [9                         Policy and monitored
 percent ROP].                                      attainment.

III. What Is Our Final Action?

    The EPA is approving a revision to the Texas SIP, which was
submitted to show attainment of the one-hour ozone standard in the El
Paso ozone nonattainment area by the applicable attainment date, but
for emissions from Mexico. The revision satisfies section 179B of the
CAA. The EPA is electing to defer the post-1996 RFP requirement. In so
doing, the EPA is finding that, based on the States's section 179B
attainment demonstration the El Paso area would attain by November 15,
1996, the State's enforceable commitment to perform basin-wide modeling
when the necessary Juarez information becomes available, and monitoring
data now showing attainment, a post-1996 plan with an additional 9
percent of reductions from November 1996 through November 1999, is not
necessary for attainment in the El Paso area.
    The EPA believes that all section 179B approvals should be on a
contingency basis. Therefore, this section 179B modeling-based approval
is valid only as long as the area's modeling data continue to show that
the El Paso ozone area would be in attainment, but for emissions from
outside the United States. If El Paso again experiences one-hour ozone
violations, or if future successful basin-wide modeling demonstrates
the El Paso area could achieve attainment of the one-hour standard
through reduction measures typically employed by serious nonattainment
areas, the EPA will review the decision to defer the 9 percent ROP
requirement, and Texas may be required to submit a new post-1996 ROP
plan for El Paso.
    The EPA is also approving El Paso's VOC and NOX motor
vehicle emissions budgets, under section 176(c) of the CAA.

*    *    *    *    *


Chapter I, title 40 of the Code of Federal Regulations is amended as follows:


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

    Authority: 42 U.S.C. 7402 et seq.

Subchapter SS--Texas

  2. The table in Sec.  52.2270(e) entitled ``EPA approved nonregulatory
provisions and quasi-regulatory measures in the Texas SIP'' is amended
by adding two entries to the end of the table to read as follows:

Sec.  52.2270  Identification of plan.

* * * * *
    (e) * * *
* * * * *

         EPA approved Nonregulatory Provisions and Quasi-Regulatory Measures in the Texas SIP
                                        Applicable        submittal/
      Name of SIP Provision           geographic  or      effective   EPA approval     Comments
                                    nonattainment area       date         date  

 Section 179B Attainment            El Paso ozone            10/03/94     6/10/04     Approval includes a
 Demonstration Report.              nonattainment area.                              revision submitted 08/09/96.

Deferral of the post 1996 RFP....  El Paso ozone         ...........     6/10/04    nonattainment area.

Enforceable commitment to conduct  El Paso ozone            10/03/94     6/10/04     additional modeling for the area nonattainment area.
 as new data become available.
 This modeling effort will be
 conducted under the auspices of
 the 1983 La Paz Agreement
 between the United States and

VOC and NOX Motor Vehicle          El Paso ozone            12/11/97     6/10/04    Emissions Budget for Conformity.   nonattainment area.

EPA Region 6 Contact:
     Bill Deese or Joe Kordzi at (214-665-7253),


This SIP Citation Was Last Modified on: 07/16/2004