Agency Highlights

United States Environmental Protection Agency (“EPA”)

EPA Proposes to Rescind Regulatory Determinations and Deadlines for Six PFAS Compounds. EPA recently published two proposed rules that would scale back portions of the “National Primary Drinking Water Regulation” (“NPDWR”) which previously established the maximum contaminant levels (“MCLs”) for six PFAS compounds. The first proposed rule, published on May 20, 2026, would extend the compliance deadline from 2029 to 2031 for public water systems to meet the MCLs for perfluorooctanoic acid (“PFOA”) and perfluorooctanesulfonic acid (PFOS). This would provide additional time for public water systems to invest in treatment, infrastructure, monitoring, and other capital improvements. The second proposed rule would rescind the regulatory determinations and individual MCLs for the four remaining PFAS compounds originally included in the NPDWR: hexafluoropropylene oxide dimer acid (“HFPO-DA,” also known as GenX), perfluorononanoic acid (“PFNA”), perfluorohexanesulfonic acid (PFHxS), and the Hazard Index MCL for mixtures of these substances plus perfluorobutanesulfonic acid (PFBS). The EPA stated that the proposed recission is the result of the agency’s prior procedural missteps and does not reflect any reassessment of the science underlying EPA’s prior MCL determinations. EPA’s public comment period on both proposed rules ended on July 20, 2026.

EPA Proposes Rule to Update PFAS Reporting and Monitoring Requirements for Publicly Owned Treatment Works Plants Under National Pollutant Discharge Elimination System (“NPDES”) Permits. The Clean Water Act (“CWA”) prohibits any person or entity from discharging any pollutant from a point source to a water of the United States unless the discharge is authorized by a NPDES permit. However, NPDES applicants are only required to report the discharge of pollutants specifically listed in the NPDES application, a list that has not been updated since 1987. The list currently does not include per- and polyfluoroalkyl substances (“PFAS”). This proposed rule would require publicly owned treatment works plants and other wastewater treatment plants to monitor and report PFAS discharges as part of the NPDES permit program. The final rule is expected in May 2027.

EPA to Begin Revisions to Establish Sixth Unregulated Contaminant Monitoring Rule for Public Water Systems. Section 1445(a)(2) of the Safe Drinking Water Act (“SDWA”) requires the EPA to establish a list of unregulated contaminants for monitoring purposes every five years. This action allows the EPA to meet the SDWA’s statutory requirement by establishing the terms for the next (sixth) cycle of monitoring and identifying the new unregulated contaminants to be monitored during the next five-year period during 2027-2031. Monitoring preparations are anticipated in 2027, with sample collection between 2028-2030 and reporting concluding in 2031. To prepare for this future action, the EPA: (1) solicited public input on the development of drinking water analytical methods for emerging contaminants in drinking water, particularly those listed on the agency’s Fifth Contaminant Candidate List, that might support monitoring efforts under the Sixth Contaminant List; (2) held a pre-proposal public webinar to discuss potential approaches to develop the Sixth Contaminant List and included time for public discussion; (3) hosted an informational webinar for Tribal government representatives to discuss the development of the Sixth Contaminant List; and (4) held an informational webinar for State representatives to discuss potential approaches to the development of the Sixth Contaminant List and the implementation of the rule. The EPA will seek public comment throughout the publication of the proposal.

EPA Prepares to Update the Water Quality Certification Rule. On July 7, 2026, the EPA finalized its update to the agency’s Water Quality Certification Rule required under Section 401 of the CWA. The CWA prohibits federal agencies from issuing a license or permit to conduct any activity that may result in a discharge into a water of the United States unless a state or authorized Tribe issues a water quality certification. The EPA last revised the Water Quality Certification Rule in 2023, and the latest proposed revisions will address challenges cited by EPA with implementing the 2023 revisions. EPA’s latest proposed revision would limit the scope of certification to a standardized list of contents required for certification requests across states, tribes, and industries. EPA expects the rule to be finalized around July 2026.

EPA Presents Draft Rule to Revise the Existing Definition of “Begin Actual Construction” and Add Definition of “Pollutant-Emitting Activities” Under the Clean Air Act. On May 11, 2026, EPA published proposed revisions to its New Source Review (“NSR”) air permitting regulations which would discern between construction of a stationary source and non-emitting components or structures. This distinction, if finalized, would allow non-emitting components or structures to be constructed prior to the owner or operator receiving an NSR air permit for a new or a major modification to a major stationary source. The current regulations prohibit these sources from “begin[ing] actual construction” without first obtaining an NSR permit, with “begin actual construction” being defined as “the initiation of physical on-site construction activities on an emissions unit which are of a permanent nature,” including ancillary construction such as installing building supports and foundations or laying underground piping. While guidance published in 2020 recommended the allowance of certain construction, the proposed rule seeks to codify current practices. This effort encompasses revision of the existing definition of “Begin Actual Construction” and adds the definition of “Pollutant-Emitting Activities” applicable to both Nonattainment New Source Review and Prevention of Significant Deterioration regulations. A virtual hearing was held on May 28, 2026, and comments were accepted through June 29, 2026. 91 Fed. Reg. 26958.

EPA Revises its Interim Guidance on the Destruction and Disposal of PFAS and Associated Materials. On April 20, 2026, EPA published updated Interim Guidance on the Destruction and Disposal of Perfluoroalkyl and Polyfluoroalkyl Substances and Materials Containing Perfluoroalkyl and Polyfluoroalkyl Substances. This update to the previously issued 2024 guidance provides slight revisions to the recommended management framework for Perfluoroalkyl and Polyfluoroalkyl (“PFAS”) materials, detailing recent practice and available technologies, thereby reducing the risk of PFAS exposure to the environment during destruction and disposal. The guidance does not provide for a specific or preferential choice, but rather an evaluation of each practice and respective ability to minimize PFAS introduction to the environment. The categories of disposal include underground injection and landfilling, with thermal treatment being the only destruction method provided.

In this revised guidance, EPA maintains its recommendation of hazardous waste landfills for disposal, citing facility controls of landfill gas and leachate that limit environmental releases. For municipal landfills, EPA does not recommend the disposal of materials containing high concentrations of volatile and soluble PFAS, finding that risk of environmental release may be higher than previously thought. However, the revised guidance still finds that municipal landfills may be appropriate disposal sites for PFAS such as Teflon. New findings since 2024 also demonstrate that certain operating conditions for thermal treatment units may effectively destroy PFAS completely and minimize human exposure and environmental release. Comments were accepted through June 29, 2026. Moving forward, the EPA Administrator announced on April 28, 2025 that EPA intends to provide annual updates, rather than the three-year updates required by the National Defense Authorization Act. 91 Fed. Reg. 22815.

EPA Withdraws Proposed Rule “Definition of Hazardous Waste Applicable to Corrective Action for Releases from Solid Waste Management Units”. On May 8, 2026, EPA withdrew its previously proposed “Definition of Hazardous Waste Applicable to Corrective Action for Releases From Solid Waste Management Units.” Originally published on February 8, 2024, the rule sought to amend the formal definition of “hazardous waste” targeting corrective action for releases originating from solid waste management units at treatment, storage, and disposal facilities permitted under the Resource Conservation and Recovery Act (“RCRA”) in an effort to help streamline oversight. The proposed rule was also designed to inject the statutory corrective action authorities into existing regulations, providing formal notice that statutory definitions themselves, rather than narrow regulatory derivatives, shall govern emerging contaminants that have not yet been officially listed, thereby expanding the scope of EPA under applicable RCRA provisions.

EPA received a significant number of public comments and after review determined that the proposed rule was inherently unnecessary as years of program implementation show that most existing corrective actions available already handle regulatory hazardous wastes and hazardous constituents that have not yet been listed or identified by regulation. Additionally, EPA has other existing regulatory tools to require cleanup in RCRA permits of any hazardous waste that are outside official listing but are a risk to human health and the environment subject to modification as deemed necessary.

EPA found that rather than simplifying the corrective action process as intended, the proposed rule would hinder implementation and likely create regulatory uncertainty, opening the door for disruption of the existing regulatory processes for facility operators. 91 Fed. Reg. 25266.

Public Utility Commission of Texas (“PUC”)

Oncor Files Unified Tracker Mechanism Application. On April 22, 2026, Oncor Electric Delivery Company LLC (“Oncor” or “Company”) filed an application with the PUC for Approval of a Single Unified Tracker Mechanism (“UTM”). The UTM, which is authorized under Public Utility Regulatory Act § 36.216, authorizes eligible utilities to file a single annual proceeding to adjust nonfuel rates on a system-wide basis to reflect changes in transmission and distribution invested capital. The UTM consolidates Oncor’s distribution cost recovery factor (“DCRF”), interim transmission cost of service, and transmission cost recovery factor. Additionally, the DCRF portion of the filing includes deferred distribution costs related to Oncor’s implementation of its Commission-approved System Resiliency Plan.

Overall, Oncor’s UTM seeks a cumulative increase in its transmission and distribution revenue requirements of at least $1 billion on the heels of the utility receiving in April a net $560 million increase in its total base rate revenue requirement. The Steering Committee of Cities Served by Oncor (“OCSC”) and stakeholders have conducted discovery on the Company’s UTM Application and are scheduled to file direct testimony in July. More information can be found in Docket No. 59249.

Ongoing Texas-New Mexico Power Company (“TNMP”) Rate Case. In November 2025, TNMP filed an Application for Authority to Change Rates. TNMP requested a net increase in transmission and distribution rates of approximately $34 million over adjusted test-year revenues, or an approximately 5% increase over the adjusted test-year revenues of $673 million. TNMP also requested a capital structure of 52.46% debt and 47.54% equity and a return on equity of 10.4%. If TNMP’s original request was approved unchanged, residential customers would have seen a monthly increase of $5.20 to their average electric bill. Cities Served by Texas-New Mexico Power Company and stakeholders conducted discovery and filed direct testimony recommending adjustments to TNMP’s Application.

On May 29, 2026, parties filed an Unopposed Stipulation and Settlement Agreement (“Agreement”). The parties agreed that TNMP’s total base revenue requirement should be set at $677.2 million, which is an increase of approximately $4.5 million when compared to the Company’s present revenues. Additionally, the Agreement proposes a revised regulatory capital structure of 55% debt and 45% equity and authorized return on equity of 9.65%.

Assuming the PUC approves the Agreement, final rates will be effective for electricity bills on and after 45 days from the date of the final order. More information can be found in Docket No. 58964.

Lone Star Transmission, LLC (“Lone Star” or “Company”) Rate Case. On February 6, 2026, Lone Star filed a Statement of Intent and Application for Authority to Change Rates. In the Application, Lone Star seeks approval of a total revenue requirement of $115,900,133, which represented a $5,785,530, or a 5.25%, increase over its current revenues. Lone Star also requested a 10.55% return on equity and a capital structure of 55% long-term debt and 45% equity. On February 10, OCSC intervened in this proceeding. This motion was granted on February 25, 2026. OCSC and other stakeholders have conducted discovery and filed direct testimony. On June 24, 2026, the parties reached a settlement in principle, and the proceeding thereafter was abated to allow the parties to prepare the necessary settlement documents. More information can be found in Docket No. 59245.

Electric Transmission Texas, LLC (“ETT” or “Company”) Rate Case. On April 20, 2026, ETT filed a Statement of Intent and Application for Authority to Change Rates. In the Application, ETT sought approval of a total revenue requirement of approximately $439.3 million, which represents a $42.1 million, or a 10.6% increase over its current revenues. ETT has also requested a 10.5% return on equity and a capital structure of 55% long-term debt and 45% equity. On April 22, 2026, OCSC intervened in this proceeding. OCSC and other stakeholders are conducting discovery while preparing their direct testimony. More information can be found in Docket No. 59642.

PUC Rulemaking Update. In January 2026, PUC Staff updated its calendar to reflect projected rulemaking timelines for the 2026 year. The calendar is a robust list of projects covering changes to the PUC’s electric and water rules. The 2026 calendar can be found on the PUC’s Interchange under Docket No. 59212.

• As of June 24, 2026, the following calendar rulemakings are in progress:
• Project No. 58481 – Rulemaking to Implement Large Load Interconnection Standards Under PURA 37.0561
• Project No. 58000 – Rulemaking to Update Wholesale and IOU Retail Transmission Cost Recovery in the ERCOT Region
• Project No. 59557 – Streamlined Complaint Process
• Project No. 59288 – Review of §25.107
• Project No. 59523 – Implementation of PURA 35.153 – TDU and PGC Contracts for Electric Energy Storage Facility Capacity
• Project No. 58482 – Rulemaking to Develop Reliability Service to Competitively Procure Demand Reductions from Large Load under PURA 39.170
• Project No. 59432 – Transmission and Distribution Pole Structural Integrity and Service Quality Standards
• Project No. 59431 – Distribution Pole Management and Inspection Plans
• Project No. 59086 – Implementation of HB 2712 (89R) – Future and Combined Test Years (Water and Sewer)
• Project No. 59564 – Review of §24.153 – Customer Requests for Water and Sewer Service Changes
• Project No. 59528 – Implementation of HB 3092 (89R) – Minimum Transmission Line Length for CCN Amendments

• The following rulemakings since the publication of the 2026 rulemaking calendar have been completed and new rules are in effect:
• Project No. 58480 – Rulemaking to Establish Large Load Criteria Forecasting Criteria PURA 37.0561
• Project No. 58434 – Rulemaking for Firm Fuel Supply
• Project No. 58400 – CY2025 Updates to Chapter 22 – Procedural Rules, Subchapters A-F
• Project No. 58401 – CY2025 Updates to Chapter 22 – Procedural Rules, Subchapters G-J
• Project No. 58402 – CY2025 Updates to Chapter 22 – Procedural Rules, Subchapters K-O
• Project No. 58392 – Implementation of SB 231 (89R) – Temporary Emergency Electric Energy Facilities
• Project No. 58391 – Implementation of SB 740 (89R) – System Improvement Charge
• Project No. 57883 – Commission Directives to ERCOT
• Project No. 58479 – Rulemaking for Net Metering Arrangements Involving a Large Load Co-Located with an Existing Generation Resource under PURA 39.169
• Project No. 59042 – Texas Energy Fund – Texas Backup Power Package Program
• Project No. 59332 – Review of §§ 24.245 and 24.259

Electric Reliability Council of Texas’ (“ERCOT”) Updates

PUC Approves ERCOT Batch Study Revision Requests. On June 18, 2026, the PUC approved ERCOT Batch Zero revision requests – PGRR145 Batch Zero Process for Large Load Interconnections and NPRR1325 Related to PGRR145, Batch Zero Process for Large Load Interconnections. This marks a significant step in Texas’ effort to manage the growing volume of large load interconnection requests.

The new rules are meant to accelerate approvals for data centers seeking to connect to the state’s power grid. More specifically, the batch study process will allow ERCOT to conduct a single interconnection study for all the loads across the system included in a particular batch. Previously, many loads found themselves in a situation where their potential impacts on the grid were subject to restudies by ERCOT because of potential offsetting impacts from nearby loads also seeking interconnections. The ERCOT Board approved the Batch Zero process framework at its June Board of Directors meeting.

According to information released by ERCOT, projects that are further along in the developmental process will be prioritized for interconnections. The first group of applicants under the new system—otherwise known as “Batch Zero”—will be notified in August whether they will be included in the batch, according to ERCOT.
“This new process represents a fundamental shift in how ERCOT manages the significant growth of large load interconnection, providing a structured, transparent path forward that protects reliability for Texans while supporting the state’s continued economic growth,” ERCOT CEO Pablo Vegas said in a prepared statement.

With the rule framework, ERCOT and the PUC hope to address the staggering influx of grid interconnection requests from data centers and other large energy consumers. Under some projections, power demand could reach anywhere from 138 gigawatts to 209 gigawatts inside ERCOT by 2030. For context, 138 GW would reflect an increase of 62 percent over ERCOT’s current peak energy use.

In addition to the new batch study framework, the rules include provisions to facilitate interconnections for large customers seeking to build their own onsite generation to self-supply some or all of their electricity. Additionally, the framework creates a pathway to connect for large customers who agree to let ERCOT curtail their power use in response to local transmission constraints.

Going forward, ERCOT expects to notify Batch Zero applicants of their project classification in August 2026, at which point the full scope of Batch Zero will be known. A final transmission plan covering the entire batch of projects across the state is expected to be published sometime in the fall of 2027. While not all interconnection requests will result in built projects, ERCOT data shows the majority expect to be operational by 2030.

“Agency Highlights” is prepared by Jake Steen in the Firm’s Districts, Water, and Litigation Practice Groups; Geno Albini in the Firm’s Air and Waste Practice Group; Jack Klug in the Firm’s Energy and Utility Practice Group; Roslyn Warner in the Firm’s Energy and Utility Practice Group; and Markel Perkins in the Firm’s Energy and Utility Practice Group. If you would like additional information or have questions related to these agencies or other matters, please contact Jake at 512.322.5811 or jsteen@lglawfirm.com, or Geno at 512.322.5868 or galbini@lglawfirm.com, or Jack at 512.322.5837 or jklug@lglawfirm.com, or Roslyn at 512.322.5802 or rwarner@lglawfirm.com, or Markel at 512.322.5855 or mperkins@lglawfirm.com.