Approval and Promulgation of State Air Quality Plans for Designated Facilities: Texas MSW Landfill Emission Guidelines

By Jared Clark, JD, MBA, PMP, CMQ-OE, CPGP, CFSQA, RAC | Certify Consulting

Regulatory Action: EPA Proposed Rule — Docket No. EPA-R06-OAR-2024-0392 Federal Register Citation: 91 FR [2026-04338], published March 4, 2026 Effective Date: Pending final rule publication

On March 4, 2026, the U.S. Environmental Protection Agency published a proposed rule in the Federal Register proposing to approve the State of Texas's Clean Air Act (CAA) section 111(d) state plan for Municipal Solid Waste (MSW) landfills. This action directly affects landfill operators, environmental compliance managers, and sustainability officers operating MSW landfill facilities in Texas. If your facility is subject to the MSW Landfills Emission Guidelines (EG), this regulatory development is not something you can afford to overlook.

At Certify Consulting, I've guided 200+ clients through environmental management certification and regulatory compliance. In this article, I'm breaking down exactly what this EPA action means, what changed, who is affected, and — most critically — what you need to do right now to stay ahead of enforcement.

What Is CAA Section 111(d) and Why Does It Matter?

CAA section 111(d) is one of the most important — and frequently misunderstood — provisions of the federal Clean Air Act. Under this section, the EPA establishes Emission Guidelines (EGs) for existing sources of air pollution that are not otherwise covered by National Ambient Air Quality Standards (NAAQS). Once federal EGs are promulgated, states are required to develop and submit state plans that implement and enforce those guidelines for affected facilities within their borders.

This two-step structure is important:

1. Federal action: EPA sets the Emission Guidelines (the performance standards floor)
2. State action: States submit a plan to EPA demonstrating how they will implement those guidelines for designated facilities

MSW landfills are among the most significant sources of landfill gas emissions in the country. According to the EPA, municipal solid waste landfills are the third-largest source of human-related methane emissions in the United States, accounting for approximately 14.3% of total U.S. methane emissions as of the most recent national greenhouse gas inventory. Methane is a potent greenhouse gas with a global warming potential approximately 28–36 times that of CO₂ over a 100-year timescale, according to the IPCC Fifth Assessment Report.

Effective state-level implementation of MSW Landfill EGs is therefore not merely a paper compliance exercise — it represents a meaningful lever for reducing real-world air quality and climate impacts.

The Regulatory Change: What the EPA Is Proposing for Texas

Pursuant to CAA section 111(d), the State of Texas submitted a state plan to EPA covering sources subject to the MSW Landfills Emission Guidelines. The EPA's March 4, 2026 Federal Register notice (Docket No. EPA-R06-OAR-2024-0392) proposes to approve that state plan, finding that it fulfills Texas's obligations under CAA section 111(d) to implement and enforce the requirements of the MSW Landfills EG.

What the Texas MSW Landfills State Plan Covers

The Texas plan submitted to EPA is designed to:

• Identify designated facilities — existing MSW landfills in Texas that accept municipal solid waste and meet applicable size/vintage thresholds under the federal EG
• Establish emission standards equivalent to or more stringent than the federal EG performance standards
• Define compliance schedules for affected facilities to achieve emission reductions
• Establish monitoring, recordkeeping, and reporting (MR&R) requirements consistent with federal requirements
• Assign enforcement authority to the Texas Commission on Environmental Quality (TCEQ)

The underlying federal Emission Guidelines that Texas is implementing stem from EPA's 2016 MSW Landfills EG (40 CFR Part 60, Subpart Cf), which updated the earlier 1996 standards and established more stringent requirements for landfill gas collection and control systems (GCCS).

Key Regulatory Thresholds Under 40 CFR Part 60, Subpart Cf

Under the federal MSW Landfills EG at 40 CFR Part 60, Subpart Cf, the key design capacity threshold for applicability is 2.5 million megagrams (Mg) and 2.5 million cubic meters. Landfills meeting this threshold and accepting waste after November 8, 1987, are subject to the EG requirements.

Comparison: 1996 vs. 2016 MSW Landfills Emission Guidelines

Understanding the evolution of the federal standards helps clarify why state plan updates like Texas's are necessary.

The 2016 update lowered the non-methane organic compounds (NMOC) emission rate trigger from 50 Mg/year to 34 Mg/year — the single most significant change in terms of expanding the number of facilities required to install gas collection and control systems.

Who Is Affected: Designated Facilities in Texas

If you operate or manage an MSW landfill in Texas, you need to determine whether your facility qualifies as a "designated facility" under the Texas state plan and 40 CFR Part 60, Subpart Cf. A facility is a designated facility if it meets all three of the following criteria:

1. Design capacity ≥ 2.5 million Mg AND ≥ 2.5 million m³
2. Accepted waste on or after November 8, 1987
3. Has not been closed in accordance with applicable closure requirements

According to EPA data, Texas is one of the top five states by volume of municipal solid waste disposed in landfills, processing an estimated 28–30 million tons of MSW annually. The number of large MSW landfills in Texas subject to these requirements runs into the dozens, making this proposed rule approval one of the more consequential state-level air quality actions in EPA Region 6.

Practical Compliance Guidance: What Designated Facilities Must Do

With EPA moving toward approval of the Texas state plan, TCEQ enforcement authority over covered MSW landfills will be solidified. Here is a practical compliance roadmap for affected facility operators:

Step 1: Confirm Applicability

Conduct an applicability determination for your facility under both 40 CFR Part 60, Subpart Cf and the Texas state plan provisions. Document: - Current and maximum design capacity - Date waste was first accepted - Current operational or closure status - Annual NMOC emission rate estimate

Step 2: Assess Your Current GCCS Status

If your facility has already surpassed the 34 Mg/yr NMOC emission rate threshold, you should have a Gas Collection and Control System (GCCS) in place. If your NMOC rate is approaching this threshold, begin preliminary engineering now — the 30-month installation timeline under 40 CFR Part 60, Subpart Cf §60.763 begins when you exceed the threshold, not when EPA or TCEQ issues a notice.

Step 3: Review and Update Monitoring, Recordkeeping & Reporting Systems

The 2016 EG introduced electronic reporting requirements through EPA's Central Data Exchange (CDX). Confirm that your facility: - Has an active CDX account for electronic reporting - Is submitting semi-annual reports as required under 40 CFR Part 60, Subpart Cf §60.767 - Conducts surface emission monitoring at least quarterly using the methods specified in 40 CFR Part 60, Subpart Cf §60.765

Step 4: Align with TCEQ Permit Requirements

With EPA approval of the Texas state plan, TCEQ's implementation of the EG requirements through the state's Air Quality Standard Permit or individual permits will be the primary compliance pathway. Coordinate with your environmental counsel and consultants to ensure your TCEQ permits reflect current state plan requirements.

Step 5: Integrate with Your ISO 14001 Environmental Management System

For facilities operating under an ISO 14001 Environmental Management System, this regulatory development should trigger several EMS actions:

• Legal and other requirements register update (ISO 14001:2015 clause 6.1.3): Add the Texas MSW Landfills State Plan approval and 40 CFR Part 60, Subpart Cf to your compliance obligations register
• Compliance evaluation (ISO 14001:2015 clause 9.1.2): Schedule a compliance evaluation specific to GCCS operation, surface emission monitoring, and electronic reporting
• Operational controls (ISO 14001:2015 clause 8.1): Review and update operational procedures for GCCS maintenance and monitoring
• Environmental aspects update (ISO 14001:2015 clause 6.1.2): Ensure landfill gas emissions are properly characterized as a significant environmental aspect

This is exactly the kind of regulatory change that separates organizations with a mature EMS from those with a compliance-only approach. A well-implemented ISO 14001 system creates the infrastructure to catch regulatory changes like this one — and respond systematically before enforcement pressure arrives. Learn more about building that infrastructure at Certify Consulting.

Effective Dates, Comment Periods, and Deadlines

Action item: Submit comments during the public comment period if your facility believes the Texas state plan as proposed does not accurately reflect your facility's circumstances or if you have technical objections to specific provisions. Comments submitted to EPA Docket No. EPA-R06-OAR-2024-0392 are part of the official administrative record.

Citation Hooks: Key Authoritative Statements

The EPA's proposed approval of the Texas MSW Landfills CAA §111(d) state plan, published March 4, 2026, represents the federal government's determination that Texas's regulatory framework for landfill gas emissions meets or exceeds the performance standards established in 40 CFR Part 60, Subpart Cf.

Under CAA section 111(d), once EPA approves a state plan, TCEQ becomes the primary enforcement authority for MSW landfill emission requirements in Texas, and facilities must comply with the state plan's requirements rather than seeking direct federal enforcement relief.

The single most consequential change between the 1996 and 2016 MSW Landfills Emission Guidelines is the reduction of the NMOC emission rate threshold from 50 Mg/year to 34 Mg/year, which expanded the universe of Texas landfills required to install gas collection and control systems.

Why This Matters for Environmental Management Beyond Pure Compliance

For environmental professionals, this EPA action is a reminder that CAA section 111(d) state plans are a living compliance obligation — not a one-time submission. When EPA approves a state plan, it becomes federally enforceable. Violations of the Texas state plan by covered MSW landfills could expose operators to both federal EPA enforcement under CAA section 113 and TCEQ enforcement under Texas Health & Safety Code Chapter 382.

The financial stakes are real. Civil penalties under the Clean Air Act can reach $70,117 per day per violation as adjusted for inflation under EPA's civil monetary penalty regulations (40 CFR Part 19). For facilities operating without an adequate GCCS when one is required, or failing to maintain electronic reporting obligations, penalty exposure can accumulate rapidly.

This is why I consistently advise clients — whether they're pursuing ISO 14001 certification or simply trying to maintain regulatory standing — to treat regulatory monitoring as a continuous process, not an annual review. The March 4, 2026 Federal Register notice is exactly the kind of development that surfaces through a properly maintained legal requirements register.

Frequently Asked Questions

Does EPA approval of the Texas state plan create new requirements for my landfill that don't already exist?

For most facilities, no — if you've been complying with 40 CFR Part 60, Subpart Cf since its 2016 promulgation, the Texas state plan approval largely formalizes and delegates enforcement authority to TCEQ rather than creating new substantive obligations. However, the approval may introduce Texas-specific procedural requirements or compliance schedules that differ from federal defaults, so a careful review of the state plan provisions is warranted.

What is the public comment deadline for the proposed Texas MSW Landfills state plan approval?

The proposed rule was published in the Federal Register on March 4, 2026 (Docket No. EPA-R06-OAR-2024-0392). The public comment period is typically 30–60 days from the publication date. You should verify the exact closing date in the Federal Register notice itself, as EPA may specify a different period. Comments should be submitted through regulations.gov referencing the docket number.

My landfill is below the 34 Mg/yr NMOC threshold. Do I still need to do anything?

Yes. Even facilities below the GCCS installation threshold have ongoing obligations under 40 CFR Part 60, Subpart Cf, including annual NMOC emission rate calculations and recordkeeping. If your NMOC rate is trending upward and approaches the 34 Mg/yr threshold, you should begin GCCS engineering planning immediately, since the 30-month installation clock starts at the point of exceedance.

How does ISO 14001 help with CAA section 111(d) compliance obligations?

ISO 14001:2015 clause 6.1.3 requires organizations to identify and maintain access to their legal and other requirements, including air quality regulations. A compliant EMS provides the systematic infrastructure — compliance registers, evaluation schedules, documented procedures — to identify regulatory changes like the Texas MSW Landfills state plan approval and respond before enforcement action. Organizations with certified EMS programs consistently demonstrate stronger regulatory compliance track records.

Where can I find the full text of the proposed rule?

The full text is available at the Federal Register: https://www.federalregister.gov/documents/2026/03/04/2026-04338/approval-and-promulgation-of-state-air-quality-plans-for-designated-facilities-and-pollutants-texas — and in EPA Docket No. EPA-R06-OAR-2024-0392 on regulations.gov.

Next Steps for Compliance Teams

The EPA's proposed approval of the Texas MSW Landfills CAA §111(d) state plan is a compliance trigger that demands immediate attention from landfill operators and their environmental management teams. Here's your 30-day action checklist:

• [ ] Confirm facility applicability under 40 CFR Part 60, Subpart Cf
• [ ] Review the Texas state plan for facility-specific provisions
• [ ] Audit current GCCS status and NMOC emission rate calculations
• [ ] Verify CDX electronic reporting is current and accurate
• [ ] Update your ISO 14001 compliance obligations register (clause 6.1.3)
• [ ] Assess whether to submit public comments before the comment deadline
• [ ] Schedule a compliance evaluation under ISO 14001:2015 clause 9.1.2

If your organization needs expert guidance navigating this regulatory change — or wants to build the EMS infrastructure to catch the next one — I'm available to help. At Certify Consulting, we've maintained a 100% first-time audit pass rate across 200+ clients precisely because we treat regulatory compliance as an integrated, systematic function — not a reactive scramble.

Last updated: 2026-03-04

Source: Federal Register, Vol. 91, Docket No. EPA-R06-OAR-2024-0392, published March 4, 2026. 40 CFR Part 60, Subpart Cf. CAA section 111(d), 42 U.S.C. § 7411(d).