Air Plan Approval; Wisconsin; Nitrogen Oxide Emissions Control Requirements

ENVIRONMENTAL PROTECTION AGENCY <CFR>40 CFR Part 52</CFR> <DEPDOC>[EPA-R05-OAR-2024-0184; FRL-11968-01-R5]</DEPDOC> <SUBJECT>Air Plan Approval; Wisconsin; Nitrogen Oxide Emissions Control Requirements</SUBJECT> <HD SOURCE="HED">AGENCY:</HD> Environmental Protection Agency (EPA). <HD SOURCE="HED">ACTION:</HD> Proposed rule. <SUM> <HD SOURCE="HED">SUMMARY:</HD> The Environmental Protection Agency (EPA) is proposing to approve Wisconsin's additions and amendments to chapters NR 400, 428, and 484 of the Wisconsin Administrative Code (Wis. Adm. Code). These changes clarify existing requirements and ensure clear and consistent implementation of Wisconsin's control requirements for emissions of nitrogen oxide (NO <E T="52">X</E> ). </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> Comments must be received on or before August 16, 2024. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> Submit your comments, identified by Docket ID No. EPA-R05-OAR-2024-0184 at <E T="03">https://www.regulations.gov</E> , or via email to a <E T="03">rra.sarah@epa.gov.</E> For comments submitted at <E T="03">Regulations.gov</E> , follow the online instructions for submitting comments. Once submitted, comments cannot be edited or removed from the docket. EPA may publish any comment received to its public docket. Do not submit electronically any information you consider to be Confidential Business Information (CBI), Proprietary Business Information (PBI), or other information whose disclosure is restricted by statute. Multimedia submissions (audio, video, etc.) must be accompanied by a written comment. The written comment is considered the official comment and should include discussion of all points you wish to make. EPA will generally not consider comments or comment contents located outside of the primary submission ( <E T="03">i.e.,</E> on the web, cloud, or other file sharing system). For additional submission methods, please contact the person identified in the <E T="02">FOR FURTHER INFORMATION CONTACT</E> section. For the full EPA public comment policy, information about CBI, PBI, or multimedia submissions, and general guidance on making effective comments, please visit <E T="03">https://www.epa.gov/dockets/commenting-epa-dockets.</E> <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> Katie Mullen, Air and Radiation Division (AR-18J), Environmental Protection Agency, Region 5, 77 West Jackson Boulevard, Chicago, Illinois 60604, (312) 353-3490, <E T="03">mullen.kathleen@epa.gov.</E> The EPA Region 5 office is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding Federal holidays. </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> Throughout this document whenever “we,” “us,” or “our” is used, we mean EPA. <HD SOURCE="HD1">I. What is the background of this SIP submission?</HD> Chapter NR 428, Wis. Adm. Code, regulates the emissions of NO <E T="52">X</E> from certain stationary sources located in Wisconsin's current ozone nonattainment areas and areas with a history of ozone nonattainment, including Kenosha, Manitowoc, Milwaukee, Ozaukee, Racine, Sheboygan, Washington, and Waukesha counties. Since the promulgation of the 2001 and 2007 revisions to chapter NR 428, Wis. Adm. Code, Wisconsin has identified several implementation issues associated with certain parts of this chapter. The purpose of Wisconsin's proposed revisions is to ensure clear and consistent implementation of NO <E T="52">X</E> control requirements in chapter NR 428. Wisconsin is not currently seeking approval of this rule as it pertains to the reasonably available control technology (RACT) requirements under the 2015 ozone national ambient air quality standard (NAAQS). EPA will be addressing RACT at a later date. <HD SOURCE="HD1">II. What is EPA's analysis of the proposed SIP revision?</HD> Wisconsin's April 10, 2024, submittal requested that EPA approve revisions to NO <E T="52">X</E> control requirements in chapters NR 400, NR 428, and NR 484 of the Wis. Adm. Code. Wisconsin's proposed revisions clarify emission limits for units using more than one type of fuel, incorporate procedures for approving a site-specific emission limit alternative to ensure that limits are achievable in practice, revise and clarify existing compliance and monitoring requirements, clarify an applicability exception, update cross references, and include definitions. <HD SOURCE="HD2"> A. Clarification of NO <E T="54">X</E> Emission Limits During Secondary Fuel Useage </HD> Wisconsin has revised sections NR 428.04(2)(i), 428.05(2)(b), 428.05(2)(f), 428.05(3)(f), 428.22(1), and 428.22(3) of the Wis. Adm. Code to clarify that a unit firing secondary fuel is not subject to emission limits and monitoring requirements when using only the secondary fuel under certain limited circumstances, which include any of the following conditions: a. The emissions unit heat input capacity or maximum design power output while utilizing the secondary fuel is less than the corresponding applicability thresholds. b. The emissions unit burns the secondary fuel only during periods of curtailment or supply interruption of other fuel(s) not to exceed 500 hours in a 12 consecutive month period. c. During periodic testing, maintenance, or operator training of the secondary fuel when the periodic testing, maintenance, or operator training does not exceed 48 hours during any calendar year. d. The secondary fuel constitutes less than 1% of the unit's fuel consumption within a 12 consecutive month period. Also, NR 428.04(4)(c), 428.05(5)(c), and 428.24(1)(c) contain the secondary fuel recordkeeping requirements. EPA is proposing that these revisions are approvable since they clarify the applicability of emission limits and monitoring requirements when a facility uses more than one type of fuel. <HD SOURCE="HD2">B. Procedures for Approving a Site-Specific Emission Limit Alternative</HD> Section NR 428.055 provides a pathway for facilities to request a site-specific emission limit if the facility demonstrates that compliance with requirements under sections NR 428.04 or 428.05 are technologically or economically infeasible. The proposed site-specific emission limit is only effective after it has been approved into the State Implementation Plan (SIP) by EPA. These revisions are approvable since they explain the steps needed to implement a site-specific alternative emission limit. <HD SOURCE="HD2">C. Clarification of Monitoring Requirements for Specific Categories of Emissions Units</HD> Wisconsin has created language under sections NR 428.08(2)(e), 428.08(2)(f), and 428.08(3) that clarifies monitoring requirements and exceptions for NO <E T="52">X</E> emissions units such as kilns, furnaces, asphalt plants, process heating units, and engines. Section NR 428.02(2)(g) incorporates an alternative to operating a continuous emissions monitoring system (CEMS) by meeting operational and performance testing requirements that are consistent with the SIP-approved compliance demonstration requirements for emission limitations under s. NR 428.23(1)(b). Section NR 428.08(2)(g)4. a. requires that emissions performance tests be conducted according to Method 7, 7A, 7B, 7C, 7D, or 7E under 40 CFR part 60, appendix A. Section NR 484.04 table 2 Row (15m), which incorporates these Federal test methods by reference, is revised to cross-reference to section NR 428.08(2)(g)(4)(a). These revisions are approvable since they clarify the monitoring requirements and exceptions for NO <E T="52">X</E> emission units subject to this rule. <HD SOURCE="HD2">D. Revision of Compliance Monitoring Plan Submittal Deadline</HD> Wisconsin has revised its deadline for compliance monitoring plan submittals under section NR 428.07(1)(a)2., Wis. Adm. Code, from “at least 180 days prior to initial operation” to “at least 180 days prior to initial operation, or an alternative date less than 180 days approved by the department.” The previous rule language required plans to be submitted 180 days before initial operation. This means a source would have been required to wait for the 180-day period to end prior to operating, even if the source was permitted and physically capable of operation prior to that date. This revised rule is approvable since it streamlines the implementation of this section by allowing the source to request an alternative date to avoid the waiting period if warranted. <HD SOURCE="HD2">E. Clarification of Exception</HD> Wisconsin's revisions clarify that the unit exception under section NR 428.21(3), Wis. Adm. Code, applies only to units constructed before August 1, 2007, as originally intended. This revision is approvable since it clarifies which emission units qualify for this exception. <HD SOURCE="HD2">F. Definitions and Cross References</HD> The proposed rule incorporates a definition for SIP, the acronym for State Implementation Plan, under section NR 400.03(4)(mf). Wisconsin has also added definitions for “primary fuel”, “secondary fuel”, “simple cycle stationary combustion turbine”, and “supply interruption” or “curtailment” under section NR 428.02(7i), (7p), (7u) and (7w). Wisconsin has also updated cross references through Ch. NR 428, Wis. Adm. Code, to be consistent with the proposed rule language. These administrative type revisions are approvable since they ensure terms included in the new rule language are defined and cross references are updated. EPA has reviewed the amendments contained in Wisconsin's submittal, as discussed in detail above, and is proposing to approve the amended portions of NR 400, 428, and 484. Because these changes provide clarity and generally strengthen the currently approved SIP, EPA is proposing that these changes will not interfere with any applicable requirement concerning attainment, reasonable further progress, or any other Clean Ai ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 16k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━