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Proposed Rule

Air Plan Approval; California; Mojave Desert Air Quality Management District; Definition of Terms

In Plain English

What is this Federal Register notice?

This is a proposed rule published in the Federal Register by Environmental Protection Agency. Proposed rules invite public comment before becoming final, legally binding regulations.

Is this rule final?

No. This is a proposed rule. It has not yet been finalized and is subject to revision based on public comments.

Who does this apply to?

Consult the full text of this document for specific applicability provisions. The affected parties depend on the regulatory scope defined within.

When does it take effect?

No specific effective date is indicated. Check the full text for date provisions.

📋 Related Rulemaking

Final Rule 2026-00208 This proposal became this final rule
Linked by: title_cfr_agency (90% confidence)

Document Details

Document Number2025-12867
TypeProposed Rule
PublishedJul 10, 2025
Effective Date-
RIN-
Docket IDEPA-R09-OAR-2022-0858
Text FetchedYes

Agencies & CFR References

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Paired Documents

TypeProposedFinalMethodConf
proposed vs_final 2025-12867 2026-00208 title_cfr_agency 90%
proposed vs_final 2025-12867 2026-00194 docket 95%
proposed vs_final 2025-12867 2026-00194 docket 95%

Related Documents (by RIN/Docket)

Doc #TypeTitlePublished
2026-00194 Final Rule Air Plan Approval; California; Mojave De... Jan 8, 2026

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Full Document Text (1,906 words · ~10 min read)

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ENVIRONMENTAL PROTECTION AGENCY <CFR>40 CFR Part 52</CFR> <DEPDOC>[EPA-R09-OAR-2022-0858; FRL-10563-01-R9]</DEPDOC> <SUBJECT>Air Plan Approval; California; Mojave Desert Air Quality Management District; Definition of Terms</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 revisions to the Mojave Desert Air Quality Management District (MDAQMD or “the District”) portion of the California State Implementation Plan (SIP). These revisions concern definitions that are necessary to implement and enforce local rules that regulate air pollution. We are proposing to approve a definitions rule under the Clean Air Act (CAA or the “Act”). We are also proposing to approve the rescission of earlier versions of this rule from the California SIP as they are no longer needed to under the CAA. We are taking comments on this proposal and plan to follow with a final action. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> Comments must be received on or before August 11, 2025. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> Submit your comments, identified by Docket ID No. EPA-R09-OAR-2022-0858 at <E T="03">https://www.regulations.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 <E T="03">Regulations.gov</E> . The EPA may publish any comment received to its public docket. Do not submit electronically any information you consider to be Confidential Business Information (CBI) 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. The 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 or multimedia submissions, and general guidance on making effective comments, please visit <E T="03">https://www.epa.gov/dockets/commenting-epa-dockets.</E> If you need assistance in a language other than English or if you are a person with disabilities who needs a reasonable accommodation at no cost to you, please contact the person identified in the <E T="02">FOR FURTHER INFORMATION CONTACT</E> section. <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> Arnold Lazarus, EPA Region IX, 75 Hawthorne St., San Francisco, CA 94105, telephone number: (415) 972-3024, email address: <E T="03">lazarus.arnold@epa.gov.</E> </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> Throughout this document, “we,” “us,” and “our” refer to the EPA. <HD SOURCE="HD1">Table of Contents </HD> <EXTRACT> <FP SOURCE="FP-2">I. The State's Submittal</FP> <FP SOURCE="FP1-2">A. What rule did the State submit?</FP> <FP SOURCE="FP1-2">B. Are there other versions of this rule?</FP> <FP SOURCE="FP1-2">C. What is the purpose of the submitted rule revision and rescissions?</FP> <FP SOURCE="FP-2">II. The EPA's Evaluation and Action</FP> <FP SOURCE="FP1-2">A. How is the EPA evaluating the rule and rescissions?</FP> <FP SOURCE="FP1-2">B. Do the rule and rescissions meet the evaluation criteria?</FP> <FP SOURCE="FP1-2">C. Public comment and proposed action</FP> <FP SOURCE="FP-2">III. Incorporation by Reference</FP> <FP SOURCE="FP-2">IV. Statutory and Executive Order Reviews</FP> </EXTRACT> <HD SOURCE="HD1">I. The State's Submittal</HD> <HD SOURCE="HD2">A. What rule did the State submit?</HD> Table 1 lists the rule addressed by this proposal with the dates that it was adopted by the local air agency and submitted by the California Air Resources Board (CARB) to the EPA. Table 2 lists the existing SIP-approved rules that the EPA is proposing to rescind with this action because they have been superseded. <GPOTABLE COLS="5" OPTS="L2,i1" CDEF="s50,12,r50,12,12"> <TTITLE>Table 1—Submitted Rule</TTITLE> <CHED H="1">Local agency</CHED> <CHED H="1">Rule #</CHED> <CHED H="1">Rule title</CHED> <CHED H="1">Amended</CHED> <CHED H="1">Submitted</CHED> <ROW> <ENT I="01">MDAQMD</ENT> <ENT>102</ENT> <ENT>Definition of Terms</ENT> <ENT>9/28/2020</ENT> <ENT>3/12/2021</ENT> </ROW> </GPOTABLE> <GPOTABLE COLS="5" OPTS="L2,i1" CDEF="s50,r40,10,r40,r50"> <TTITLE>Table 2—Rules for Which Rescission From the SIP is Requested</TTITLE> <CHED H="1">Rule to rescind</CHED> <CHED H="1">Adopted</CHED> <CHED H="1">Submitted to the EPA</CHED> <CHED H="1"> <E T="02">Federal</E> <E T="02">Register</E> citation </CHED> <CHED H="1">Superseded by</CHED> <ROW> <ENT I="01">San Bernardino County Air Pollution Control District (SBCAPCD) Rule 102—Definitions</ENT> <ENT>7/5/1977</ENT> <ENT>11/4/1977</ENT> <ENT>43 FR 59489; December 21, 1978</ENT> <ENT>SBCAPCD Rule 102 at 40 CFR 52.220(c)(179)(i)(B)(1).</ENT> </ROW> <ROW> <ENT I="01">Riverside County Air Pollution Control District (RCAPCD) Rule 102—Definitions</ENT> <ENT>Not available</ENT> <ENT>11/4/1977</ENT> <ENT>43 FR 59489, December 21, 1978</ENT> <ENT>South Coast AQMD Rule 102 at 40 CFR 52.220(c)(44)(v)(A).</ENT> </ROW> </GPOTABLE> On September 12, 2021, the submittal for MDAQMD Rule 102 was deemed by operation of law to be complete. The submittal meets the completeness criteria in 40 CFR part 51, appendix V. <HD SOURCE="HD2">B. Are there other versions of this rule?</HD> We approved the prior version of MDAQMD Rule 102 into the SIP on November 12, 2020 (85 FR 71846). The prior version of MDAQMD Rule 102 was amended on January 28, 2019, and CARB submitted it to us on August 19, 2019. If approved, the current version of MDAQMD Rule 102 would replace the prior SIP-approved version of the rule. In addition, there are other outdated versions of Rule 102 (as listed in table 2) that apply within the MDAQMD that we are proposing to remove from the MDAQMD portion of the SIP because they have been superseded. <HD SOURCE="HD2">C. What is the purpose of the submitted rule revision and rescissions?</HD> Section 110(a) of the CAA requires states to submit regulations that control emissions of various air pollutants such as volatile organic compounds, oxides of nitrogen, and particulate matter. MDAQMD Rule 102 contains definitions that are necessary to implement and enforce rules that regulate air pollution within the MDAQMD. MDAQMD made numerous clarifying revisions to Rule 102 that will improve implementation of its air program. The purpose of the requested rule rescissions is to eliminate any legal confusion regarding the applicability of rules in the MDAQMD that have been superseded but that remain in the SIP. Our technical support document (TSD) evaluates the revisions to Rule 102 and the requested rescissions. <HD SOURCE="HD1">II. The EPA's Evaluation and Action</HD> <HD SOURCE="HD2">A. How is the EPA evaluating the rule and rescissions?</HD> Rules in the SIP must be enforceable (see CAA section 110(a)(2)), must not interfere with applicable requirements concerning attainment and reasonable further progress or other CAA requirements (see CAA section 110(l)), and must not modify certain SIP control requirements in nonattainment areas without ensuring equivalent or greater emissions reductions (see CAA section 193). Guidance and policy documents that we used to evaluate enforceability, relaxation, and rule stringency requirements for the applicable criteria pollutants include the following: 1. “State Implementation Plans; General Preamble for the Implementation of Title I of the CAA Amendments of 1990,” 57 FR 13498 (April 16, 1992); 57 FR 18070 (April 28, 1992). 2. “Issues Relating to VOC Regulation Cutpoints, Deficiencies, and Deviations,” EPA, May 25, 1988 (the Bluebook, revised January 11, 1990). 3. “Guidance Document for Correcting Common VOC & Other Rule Deficiencies,” EPA Region 9, August 21, 2001 (“the Little Bluebook”). <HD SOURCE="HD2">B. Do the rule and rescissions meet the evaluation criteria?</HD> Based on our review, MDAQMD Rule 102 and the rescission of SBCAPCD Rule 102 and RCAPCD Rule 102 meet applicable CAA requirements and are consistent with relevant guidance regarding enforceability and SIP revisions. The TSD has more information on our evaluation. <HD SOURCE="HD2">C. Public comment and proposed action</HD> As authorized in section 110(k)(3) of the Act, the EPA proposes to approve the submitted rule in table 1 because it fulfills all relevant requirements. If approved, the rule in table 1 would replace the current version of the rule in the SIP. Additionally, as authorized in section 110(k)(3) of the Act, the EPA proposes to approve the rescission of the rules in table 2 from the MDAQMD portion of the California SIP because they are no longer needed to meet any CAA requirement and because rescission would not interfere with reasonable further progress or attainment of any of the NAAQS. We will accept comments from the public on this proposal until August 11, 2025. If we finalize approval, we will incorporate the rule and rescissions into the federally enforceable SIP. <HD SOURCE="HD1">III. Incorporation by Reference</HD> In this document, the EPA is proposing to include in a final EPA rule regulatory text that includes incorporation by reference. In accordance with requirements of 1 CFR 51.5, the EPA is proposing to incorporate by reference MDAQMD Rule 102, “Definition of Terms,” amended on September 28, 2020, that states the definitions of terms used ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 14k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
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