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Approval and Promulgation of Section 182(f) Exemption to the Nitrogen Oxides (NO<INF>X) Control Requirements for the Calcasieu Parish Ozone Nonattainment Area; Louisiana
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[Federal Register: June 13, 1996 (Volume 61, Number 115)] [Proposed Rules] [Page 30024-30028] From the Federal Register Online via GPO Access [wais.access.gpo.gov]
ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 52 [LA-22-1-6870; FRL-5520-4] Approval and Promulgation of Section 182(f) Exemption to the Nitrogen Oxides (NO<INF>X) Control Requirements for the Calcasieu Parish Ozone Nonattainment Area; Louisiana AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed rulemaking.
SUMMARY: The EPA proposes to approve a petition from the State of Louisiana requesting that the Calcasieu Parish marginal ozone nonattainment area be exempt from applicable NO<INF>X control requirements of section 182(f) of the Clean Air Act (Act). The section 182(f) NO<INF>X requirement from which the area will be exempt is NO<INF>X new source review (NSR). In addition, approval of the section 182(f) petition would remove the NO<INF>X general conformity provisions and the NO<INF>X build/no build provisions of the transportation conformity rule (for conformity provisions, see the November 24, 1993 and November 30, 1993 Federal Register). The exemption for conformity NO<INF>X requirements is found, generally, in 40 CFR part 93, subparts T and W. The section 182(f) NO<INF>X provisions are explained fully in the EPA's NO<INF>X Supplement to the General Preamble, published in the Federal Register (FR) on November 25, 1992. The State of Louisiana made the request for Calcasieu Parish based on a demonstration that additional NO<INF>X reductions would not contribute to ozone attainment in the nonattainment area. DATES: Comments on this proposed action must be received in writing on or before July 15, 1996. ADDRESSEES: Written comments on these actions should be addressed to Mr. Thomas Diggs, Chief, Planning Section, at the EPA Regional Office listed below. Copies of the documents relevant to these proposed actions are available for public inspection during normal business hours at the following locations. The interested persons wanting to examine these documents should make an appointment with the appropriate office at least 24 hours before the visiting day. U.S. Environmental Protection Agency, Region 6, Air Planning (6PD-L), 1445 Ross Avenue, Suite 700, Dallas, Texas 75202-2733. Louisiana Department of Environmental Quality, N.B. Garlock Building, 7290 Bluebonnet, Baton Rouge, Louisiana 70810. FOR FURTHER INFORMATION CONTACT:
Mr. Matthew Witosky or Mr. Quang Nguyen, Planning Section (6PD-L), Multimedia Planning and Permitting Division, U.S. EPA Region 6, 1445 Ross Avenue, Dallas, Texas 75202-2733, telephone (214) 665-7214. SUPPLEMENTARY INFORMATION: Background NO<INF>X are precursors to ground level (tropospheric) ozone, or urban ``smog.'' When released into the atmosphere, NO<INF>X will react with volatile organic compounds (VOC) in the presence of sunlight to form ozone. Tropospheric ozone is an important factor in the nation's urban air pollution problem.
Calcasieu Parish, Louisiana, was designated nonattainment for ozone and classified as marginal pursuant to sections 107(d)(4) and 181(a) of the Act. Under section 181(a), marginal areas must attain the National Ambient Air Quality Standard for ozone (the ozone standard) by November 15, 1993. Please reference 56 FR 56694 (November 6, 1991, codified for Louisiana at 40 CFR 81.319).
The Amendments to the Act (1990 Amendments) made significant changes to the air quality planning requirements for areas that do not meet the ozone standard. Subparts 1 and 2 of part D, title I of the Act contain the air quality planning requirements for ozone nonattainment areas. Title I includes new requirements to control NO<INF>X emissions in certain ozone nonattainment areas and ozone transport regions. Section 182(f) requires States to apply the same control requirements to major stationary sources of NO<INF>X as are applied to major stationary sources of VOC. For marginal areas, the NO<INF>X requirement is to provide for nonattainment new source review (NSR). In addition, there are new NO<INF>X requirements under the general and transportation conformity provisions of section 176(c). This approval exempts the area from the section 182(f) NSR NO<INF>X requirements (see the NO<INF>X Supplement to the General Preamble 57 FR 55620), and from the NO<INF>X requirements of the general, as well as the NO<INF>X requirements of the build/no build provisions of the transportation, conformity rules (see also 58 FR 63214 published on November 24, 1993 and 58 FR 62188 published on November 30, 1993, as amended, particularly at 60 FR 44790, 44794, of August 29, 1995). Applicable EPA Guidance The Act specifies in section 182(f) that if one of the conditions listed below is met, the new NO<INF>X requirements would not apply:
- In any area, the net air quality benefits are greater without NO<INF>X reductions from the sources concerned;
- In a nontransport region, additional NO<INF>X reductions would not contribute to ozone attainment in the nonattainment area; or
- In a transport region, additional NO<INF>X reductions would not produce net ozone benefits in the transport region. In addition, section 182(f)(2) states that the application of the new NO<INF>X requirements may be limited to the extent that any portion of those reductions are demonstrated to result in ``excess reductions'' of NO<INF>X. The previously-described NO<INF>X provisions of the conformity rules would also not apply in certain areas that are granted a section 182(f) exemption (see amendment to transportation conformity rule and associated explanation at 60 FR 44794). In addition, certain NO<INF>X provisions of the I/M rule would not apply in an area that is granted a section 182(f) exemption (see 57 FR 52989). The EPA's Guideline for Determining the Applicability of Nitrogen Oxides [[Page 30025]] Requirements Under Section 182(f) (December 1993), and 2 revisionary memoranda signed by John S. Seitz, Director of the EPA Office of Air Quality Planning and Standards, dated May 27, 1994 and February 8, 1995, describe how the EPA will interpret the NO<INF>X exemption provisions of section 182(f). As described more fully in the Seitz memoranda, petitions submitted under section 182(f)(3) are not required to be submitted as State Implementation Plan (SIP) revisions. Consequently, the State is not required under the Act to hold a public hearing in order to petition for an area-wide NO<INF>X exemption determination. Similarly, it is not necessary to have the Governor submit the petition.
It should be noted with respect to the application of section 182(f) NO<INF>X waivers to certain NOx requirements of the transportation conformity rule that the EPA has revised the transportation conformity rule to ensure consistency with section 176(c) (see especially 60 FR 44790, 44794). This rule revision requires areas subject to section 182(b)(1) (moderate and above, but not marginal ozone nonattainment areas) to submit transportation conformity NO<INF>X exemption requests as revisions to the SIP. Because Calcasieu is classified as marginal, the revision addressing 182(b)(1) is not applicable. State Submittal On October 28, 1994, the Louisiana Department of Environmental Quality (LDEQ) submitted to the EPA a petition pursuant to section 182(f) which requests that the Calcasieu Parish nonattainment area be exempted by the EPA from the NO<INF>X control requirements of section 182(f) of the Act. On December 21, 1995, the Governor of Louisiana submitted a request for redesignation of the area to attainment which contained additional information relevant to the State's NO<INF>X exemption petition. The request for redesignation is currently under review and will be addressed in a separate rulemaking action. The State's NO<INF>X waiver petition was based on urban airshed modeling (UAM). Subsequently, an analysis of ambient air quality data (``clean air data'') indicates that the area is currently in attainment of the ozone standard, prompting the state to submit a request that the area be redesignated as attainment. The state's modeling and monitoring data together demonstrate that additional NO<INF>X reductions would not contribute to attainment of the ozone standard in the area. Overall, this demonstration is consistent with the EPA's section 182(f) guidance. The State's submission includes a letter from Gustave Von Bodungen, Assistant Secretary of the LDEQ, to Jane N. Saginaw, Regional Administrator of the EPA Region 6, and LDEQ's summary of the State's photochemical grid modeling results. Further, the State's submission requesting redesignation to attainment for Calcasieu Parish contains quality-assured and quality-controlled data showing attainment of the ozone standard. This data is for the three-year time period of 1993 to 1995. Analysis of State Submission The following items are the basis for the EPA's action proposing to approve the State of Louisiana's section 182(f) NO<INF>X exemption petition for the Calcasieu Parish ozone nonattainment area. Please refer to the EPA's Technical Support Document and the State's submittal for more detailed information. A. Consistency With EPA Section 182(f) Guidance Chapter 4 of the EPA's December 1993 section 182(f) guidance states that the typical procedure for demonstrating that additional NO<INF>X reductions would not contribute to ozone attainment is to utilize photochemical grid modeling, such as UAM, to simulate conditions resulting from three emission reduction scenarios: (1) Substantial VOC reductions; (2) substantial NO<INF>X reductions; and (3) both VOC and NO<INF>X reductions. To demonstrate that NO<INF>X reductions are not beneficial to attainment, the area-wide predicted maximum 1-hour ozone concentration for each day modeled under scenario (1) must be less than or equal to that from scenarios (2) and (3) for the same day. Chapter 7 specifies that the application of UAM should be consistent with the techniques specified in the EPA ``Guideline on Air Quality Models (Revised),'' and ``Guideline for Regulatory Application of the UAM (July 1991).'' This guidance specifically applies to moderate and higher classification ozone nonattainment areas. As discussed in the following sections, the EPA believes that the State's UAM demonstration together with the ambient air quality data showing that the area is attaining the ozone standard support the granting of an exemption from the NO<INF>X requirements of section 182(f) of the CAA. B. UAM Modeling Analysis Although many ozone nonattainment areas used photochemical grid modeling that was required by the Act for their attainment demonstrations to apply for a NO<INF>X exemption as a marginal nonattainment area, the Act did not require Calcasieu Parish to perform such modeling for the purpose of an attainment demonstration. Thus, where such an area can make an adequate showing of the effects of NO<INF>X reductions with respect to attainment through alternative means that are otherwise consistent with relevant guidance, EPA could approve the area's demonstration.
The LDEQ submitted the results of a photochemical grid modeling exercise that was carried out, in conjunction with Calcasieu's attainment efforts, to determine if the Calcasieu area was the object of ozone and precursor transport. Although the modeling utilized for this exercise does not precisely replicate the procedures EPA guidance suggests be used to support a 182(f) exemption petition. However, the EPA believes the modeling analysis that was performed by LDEQ when combined with the area's clean air data is comprehensive enough to use in determining if the area should receive an exemption. The LDEQ used UAM version IV, an EPA-approved photochemical grid model, to develop the attainment demonstration for Calcasieu Parish. The State's modeling activities were performed in accordance with the EPA's ``Guideline for Regulatory Application of the Urban Airshed Model.'' The discussion below summarizes the EPA's analysis on how the State's modeling demonstrations complied with the EPA's guidance. Please refer to the EPA's Technical Support Document for more detailed information.
- Episode Selection
The State used the EPA ``Guideline For Regulatory Application of The Urban Airshed Model'' to select episodes for use in the Calcasieu Parish UAM modeling exercises. Data from 1991 and 1992 were examined for episodes which cover at least 48 consecutive hours and the worstcase meteorological conditions. Three episodes from 1992 were selected for the UAM analysis for the area.
Episodes selected for the Lake Charles modeling represent three different meteorological regimes which can be characterized as exhibiting potential for transport of pollutants from source areas near Baton Rouge to the Lake Charles area, absence of transport potential, and potential for transport from areas in Texas.- Model Domain and Meteorological Input The LDEQ used a large modeling domain for Calcasieu Parish to ensure that the model captured the movement [[Page 30026]] of VOC and NO<INF>X emissions generated by the surface sources. The domain covers all or part of seven counties in Texas and eight parishes in Louisiana. The domain modeled encompassed 32,000 square kilometers of surface area. Meteorological data were collected from numerous monitoring stations in the area. The LDEQ followed the methods described in the UAM User's Guides to develop model inputs for wind field data, mixing heights, temperature, and meteorological scalars for the areas. Data was obtained from the Aerometric Information and Retrieval System (AIRS), LDEQ data gathering activities, the Texas Natural Resource Conservation Commission (TNRCC), and other direct measurement techniques.
3. Boundary and Initial Conditions
LDEQ used the air quality data collected at monitoring stations throughout the domain to construct the initial conditions of the model exercise. Some default values were used where actual measurements were not available. The applied boundary conditions were developed to measure possible transport into the area from the east and west. 4. Emissions Inventory
The Calcasieu Parish modeling exercises were conducted using VOC and NO<INF>X emission inventories compiled by survey and direct measurement by the LDEQ. The modeling emissions inventories are composed of point source, area, on-road mobile, off-road mobile, and biogenic emissions. Where applicable, emissions were adjusted for pertinent conditions related to the episode day to be modeled, thus producing day-specific emissions. The EPA procedures for developing episode-specific emission inventories were followed. For Calcasieu Parish, the LDEQ developed three emission inventories for all three episodes modeled. Although the projected inventory does not reflect the attainment year for the area, the inventory projected for 1993 does not differ significantly from 1991 and 1992 inventories. Hence, the EPA believes the State's analysis still provides a valid technical basis to evaluate the NO<INF>X contributions. 5. Model Performance
For all UAM activities, model performance is measured quantitatively and qualitatively. The EPA has issued guidelines to statistically measure accuracy. In addition, the EPA strongly recommends that agencies submit graphical analysis, as a complement to statistical analysis. While the EPA has recommended ranges for statistical accuracy, there are no rigid criterion to accept or reject a model exercise. Similarly, qualitative characterizations such as good, satisfactory, fair, or poor describe the EPA's best professional judgment about graphed model performance, but are not used to grade the model exercise as acceptable or unacceptable. Based on the above criteria, the Calcasieu model performance was satisfactory. Both graphical and statistical performance measures were employed for all meteorological episodes and monitoring networks. Sensitivity analysis was also conducted to assess the stability of the models across a range of possible input parameters. For the August 20-21, 1991 episode, two of the three EPA-criterion statistical measures obtained for the area are well within the EPA's recommended ranges for good model performance (see Table 2 of the technical support document). For the April 7-8, 1992 episode, the statistical analysis for the primary day, April 8, indicates fair model performance. The statistical measures were well within the EPArecommended ranges for the primary episode day. However, simulated maximum concentrations are, in general, lower than observed peak concentrations. For the April 20-21, 1992 episode, the model performance is good. The statistical measures all fall within the EPArecommended ranges, and the temporal profiles of many sites were fairly well simulated.
Both graphical and statistical performance measures were used to evaluate the model. Using these analyses, the predicted results from the model were compared to the observed results for each episode. These analyses indicate that the model performed satisfactorily for the three episodes used for the UAM demonstration. 6. Section 182(f) Demonstration
As noted previously, Calcasieu Parish is a marginal ozone nonattainment area and EPA's NO<INF>X exemption guidance does not fully address the requirements for less than moderate nonattainment areas that were not required to utilize photochemical grid modeling for their attainment demonstrations. For purposes of their 182(f) demonstration, the LDEQ modeled the three episodes discussed above under a substantial NO<INF>X reduction strategy only. The VOC-only and VOC plus NO<INF>X reduction modeling strategies listed in EPA guidance were not performed. EPA nonetheless feels that the State's UAM demonstration in combination with the area's ambient air quality data provide adequate justification for proposing approval of the NO<INF>X exemption petition. The justification related to clean air quality data is discussed in Section C of this notice.
The LDEQ's modeling considered across-the-board reductions in the projected NO<INF>X point source emission inventories. The State modeled 50 and 25 percent emission reductions in the NO<INF>X point sources inventory for each of the three episode-days. This generated six different sensitivity tests to gauge the direction and intensity of the atmospheric reaction to NO<INF>X reductions. The State modeled 25 percent NO<INF>X reductions to characterize the effect of NO<INF>X control strategies that could have a more immediate impact. For all three episodes at 25 and 50 percent reductions, the results for the controlling day show that domain-wide predicted maximum ozone concentrations increase as the NO<INF>X reductions are applied. As explained in the EPA's 182(f) guidance, the EPA believes it is appropriate to focus this analysis on the area-wide maximum 1-hour predicted ozone concentration, since this value is critical for the typical attainment demonstration. For all three episodes, the controlling day showed that the domain-wide predicted maximum ozone concentrations are lower without NO<INF>X reductions. The model results lead to the conclusion that NO<INF>X reductions would increase the domain-wide maximum ozone concentrations. Please refer to the EPA's Technical Support Document for more detailed information. C. Clean Data Eligibility for NO<INF>X Exemption On December 21, 1995, the EPA received a request from the State to redesignate the Calcasieu area to attainment. The request for redesignation is based upon three years of quality-assured monitoring data that show no violations of the ozone standard. The data that constitute the substance of the redesignation request is available to the EPA through the Aerometric Information and Retrieval System (AIRS). Since the data were not available when the State initially requested a NO<INF>X exemption, the State chose to base its waiver request on modeling data. Now that monitoring data are available, the EPA believes it is appropriate to consider the air quality data in conjunction with the modeling information contained in the State's NO<INF>X exemption petition in determining whether to approve the State's NO<INF>X exemption request. Moreover, since the [[Page 30027]] EPA's NO<INF>X guidance provides for granting NO<INF>X exemptions based solely on clean air data, the State could have resubmitted a request for a NO<INF>X waiver based only on clean data. However, rather than having the state resubmit an additional petition, the EPA decided that the air quality data and modeling information already before the Agency, when analyzed in combination, constituted an adequate basis to propose approval of the waiver request. The EPA will act upon the State's request for redesignation in a subsequent notice. An EPA review of the AIRS ambient air quality data concluded that no violations of the ozone standard occurred in the area from 1993 through 1995. Since the absence of such violations over a 3-year period indicates that an area is in attainment of the ozone standard, this data provides further support for the conclusion that the section 182(f) test is met. This is true because for an area, like Calcasieu, that is already attaining it is clear that additional reductions of oxides of nitrogen would not contribute to ozone attainment in that area. ``Guideline for Determining the Applicability of Nitrogen Oxide Requirements Under section 182(f)'' December 1993. See the TSD for additional information regarding the area's air quality data. Proposed Rulemaking Action In this action, the EPA proposes to approve the 182(f) NO<INF>X exemption petition submitted by the State of Louisiana for the Calcasieu Parish ozone nonattainment area. The EPA believes that all section 182(f) exemptions that are approved should be approved only on a contingent basis. As described in the EPA's NO<INF>X Supplement to the General Preamble (57 FR 55628, November 25, 1992), the EPA would rescind a NO<INF>X exemption in cases where NO<INF>X reductions were later found to be beneficial in the area's attainment plan. That is, a modeling based exemption would last for only as long as the area's modeling continued to demonstrate attainment without the additional NO<INF>X reductions required by section 182(f). Similarly, if an area that received an exemption based on clean air quality data which shows that the area is attaining the ozone standard experiences a violation prior to redesignation of the area to attainment, the exemption would no longer be applicable.
If the EPA later determines, based on new photochemical grid modeling that NO<INF>X reductions would be beneficial in Calcasieu Parish, or because of an ozone violation, the area would be removed from exempt status and would be required to adopt the applicable NO<INF>X provisions of the NSR and conformity rules except to the extent that NO<INF>X reductions are shown to be ``excess reductions.'' In the rulemaking action which removes the exempt status, the EPA would provide specific information regarding the reapplication of the NSR rules and the conformity rules.
The subsequent modeling analyses mentioned above need not be limited to the purpose of demonstrating attainment as required by section 182(c)(2)(A). For example, an area might want to consider a strategy that phases in NO<INF>X reductions only after certain VOC reductions are implemented. As improved emission inventories and ambient data become available, areas may choose to remodel. In addition, alternative control strategy scenarios might be considered in subsequent modeling analyses in order to improve the cost-effectiveness of the attainment plan.
In summary, the UAM modeling results together with ambient air quality data showing no violations of the ozone standard during the last 3 years in Calcasieu Parish support the conclusion that additional NO<INF>X reductions would not contribute to attainment of the ozone standard in this area. The EPA therefore proposes to approve a NO<INF>X exemption for the Calcasieu Parish area. Approval of this petition means that the area is exempt from new source review for sources of NO<INF>X, the NO<INF>X requirements of the general conformity rule, and the NO<INF>X ``build/no build'' provisions of the transportation conformity rule (see 58 FR 63214 and 58 FR 62188). This exemption will remain effective for only as long as modeling continues to show that NO<INF>X control activities would not be beneficial in the Calcasieu Parish nonattainment area, and/or so long as, prior to redesignation to attainment, the area does not violate the ozone standard. Request for Public Comments The EPA requests comments on all aspects of this proposal. As indicated at the outset of this action, the EPA will consider any comments received by July 15, 1996. Regulatory Process Under the Regulatory Flexibility Act, 5 U.S.C. 600 et. seq., the 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, the EPA may certify that the rule will not have a significant economic 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 of less than 50,000.
Approvals of NO<INF>X exemption petitions under section 182(f) of the CAA do not create any new requirements. Therefore, because the Federal approval of the petition does not impose any new requirements, the EPA certifies that it does not have a significant impact on affected small entities. Moreover, due to the nature of the FederalState relationship under the CAA, preparation of a regulatory flexibility analysis would constitute Federal inquiry into the economic reasonableness of State action. The CAA forbids the EPA to base its actions concerning SIP's on such grounds [Union Electric Co. v. U.S. E.P.A. , 427 U.S. 246, 256-66 (S. Ct. 1976); 42 U.S.C. 7410 (a)(2)]. The Office of Management and Budget has exempted this action from review under Executive Order 12866. Unfunded Mandates Under sections 202, 203, and 205 of the Unfunded Mandates Reform Act of 1995 (``Unfunded Mandates Act''), signed into law on March 22, 1995, EPA must undertake various actions in association with proposed or final rules that include a Federal mandate that may result in estimated costs of $100 million or more to the private sector, or to State, local, or tribal governments in the aggregate. Through submission of this state implementation plan or plan revision, the State and any affected local or tribal governments have elected to adopt the program provided for under section 110 of the Clean Air Act. These rules may bind State, local and tribal governments to perform certain actions and also require the private sector to perform certain duties. To the extent that the rules being approved by this action will impose no new requirements, such sources are already subject to these regulations under State law. Accordingly, no additional costs to State, local, or tribal governments, or to the private sector, result from this action. EPA has also determined that this action does not include a mandate that may result in estimated costs of $100 million or more to State, local, or tribal governments in the aggregate or to the private sector. List of Subjects in 40 CFR Part 52 Environmental protection, Air pollution control, Hydrocarbons, Intergovernmental relations, Nitrogen dioxide, Ozone, Volatile organic compounds. Authority: 42 U.S.C. 7401-7671q. [[Page 30028]] Dated: June 7, 1996.
Carol M. Browner, Administrator.
[FR Doc. 96-15034 Filed 6-12-96; 8:45 am] BILLING CODE 6560-50-P