On July 24, 2026, the Advisory Council on Historic Preservation (“ACHP”) voted to advance a draft Notice of Proposed Rulemaking (“NPRM”) that would make sweeping amendments to its regulations implementing Section 106 of the National Historic Preservation Act (“NHPA”). If finalized, they would be the most significant rewrite of the Section 106 process since ACHP’s last major revisions in 2000. Framed as implementing Executive Order 14192’s deregulatory mandate and responding to Section 106 reviews that can stretch nearly seven years, the proposal touches nearly every stage of the process: what counts as a historic property, what effects agencies must weigh, who has a seat at the table, and how fast a project can move.
The draft NPRM has not yet been published in the Federal Register. It must first undergo review by the Office of Information and Regulatory Affairs (“OIRA”) within the White House Office of Management and Budget. OIRA review and Federal Register publication could occur as early as August or September 2026, with the 30-day comment period closing roughly 30 days thereafter. Given the scope of the changes and ACHP’s explicit invitation for data-driven feedback, project proponents would benefit by beginning to prepare comments now so they are ready to submit as soon as the comment window opens.
Background: The Leaked Draft & How We Got Here
The path to the July 24 vote was unusually compressed—and controversial. In January 2026, ACHP Vice Chairman Travis Voyles announced an intent to revisit the Section 106 regulations, emphasizing collaboration with Council members and the broader preservation community. In February 2026, ACHP established a working group and invited member participation. On June 4, 2026, the full Council adopted a resolution directing staff to develop a regulatory timeline within 30 days and providing members 60 days to submit additional comments before any proposed rule was formulated.
That timeline never materialized. Instead, on July 17, 2026, Vice Chairman Voyles circulated a nearly complete draft rewrite of 36 C.F.R. part 800 to Council members and called for an unassembled (email) vote within one week—bypassing the previously outlined deliberative process. Although the draft was stamped “Not Public,” it leaked almost immediately and was widely shared on social media and among preservation and industry stakeholders. Several Council members and organizations—including the National Conference of State Historic Preservation Officers and the National Association of Tribal Historic Preservation Officers—voted no or publicly objected to the truncated process, arguing that Tribal Nations and other stakeholders were denied a meaningful opportunity to review changes of this magnitude. Nonetheless, on July 24 the draft NPRM was approved by a vote of 16 in favor, 5 opposed, and 2 abstentions.
The draft NPRM has now proceeded to OIRA for interagency review, a required step before Federal Register publication. ACHP has not published a confirmed schedule for any step after OIRA review. On an accelerated timeline, project Federal Register publication could occur in August 2026, with the 30-day comment period closing in September 2026, a final rule potentially published by late 2026 or early 2027, and the rule taking effect 30 days after that. Under a more standard timeline, a final, effective rule would more realistically be expected in mid-to-late 2027 or later. Legal challenges after a final rule is published could further extend the period before the rule is settled.
The following summarizes the key substantive changes in the leaked draft. Given the scope of the changes and ACHP’s explicit invitation for data-driven feedback, the leaked NPRM presents a real opportunity for project proponents to shape the final rule—not just react to it. Because the public comment window may be short and open on relatively brief notice, proponents can use the time before publication to prepare. Importantly, however, because the draft NPRM could be revised during OIRA review, the draft described below should not be assumed to reflect the published version if and when it is released.
- Narrower Definitions Shrink What Counts as a “Historic Property” or an “Effect”
The draft NPRM would sharply narrow the effects agencies must consider. Most notably, it would revise the criteria for “adverse effect” by removing references to indirect and cumulative effects, instead limiting “adverse effects” to “only those reasonably foreseeable effects that have a reasonably close causal relationship to the undertaking.” These potential modifications track recent changes to federal environmental reviews that stem from the Supreme Court’s decision in Seven County Infrastructure Coalition v. Eagle County, 605 U.S. 168 (2025) and corresponding changes to National Environmental Policy Act (“NEPA”) guidance.
The draft would also delete two current examples of adverse effects: “[c]hange of the character of the property’s use or of physical features within the property’s setting that contribute to its historic significance,” and “[i]ntroduction of visual, atmospheric or audible elements that diminish the integrity of the property’s significant historic features.” In parallel, the draft NPRM would narrow the definition of “area of potential effects” to encompass only direct effects. Those potential deletions would walk back a 2019 ACHP memo that clarified that direct effects could also include visual, auditory, or atmospheric impacts.
The proposed definition of “historic property” would also be narrower. It would require a property, including a Tribal historic property, to include or have included tangible human improvements, or to have been the location of specific human activities, and to be geographically compact. Read literally, that could exclude the broad traditional cultural properties (“TCPs”), sacred landscapes, mountains, and rivers that many Tribes rely on Section 106 to protect. - The Agency Official Gets the Pen, Public & Tribal Participation Become Discretionary, and Applicants Become Consulting Parties
The draft NPRM would strip out most of the regulatory detail on Tribal consultation, leaving the agency’s underlying statutory duty intact but far less defined in the text agencies actually follow day to day. Specifically, Tribal Historic Preservation Officers (“THPOs”) and State Historic Preservation Officers (“SHPOs”) would no longer play a role in identifying historic properties, assessing impacts, and recommending avoidance or mitigation measures as an initial matter. Instead, the agency official would prepare a “Section 106 report” that identifies historic properties, assesses impacts, and makes a determination on next steps. This Section 106 report would then be circulated to SHPOs, THPOs, and all relevant consulting parties—including project proponents—who would have an opportunity to comment on the findings. The agency official must review those comments but has no obligation to respond to or incorporate any before issuing the final memorandum of decision (“MOD”). That MOD would largely replace today’s negotiated “memorandum of agreement” (“MOA”) process, shifting Section 106 from a consensus-seeking exercise to one where the agency official simply decides. Notably, in the draft NPRM, the ACHP proposes to ask the public whether the MOA process should survive as an alternative path—a question that may prompt significant public response.
Similarly, public comment would shift from mandatory to optional, on the theory that Section 106 itself only guarantees comment rights to the ACHP, not the public at large. That said, ACHP would ask potential commenters whether public participation may still be useful where it can surface community concerns early and reduce litigation risk.
And finally, applicants for federal funding or permits subject to Section 106 consultation would now be invited to become consulting parties. - More Off-Ramps, Exemptions & NEPA Alignment
The proposal would also borrow from the NEPA playbook. It would encourage procedures that function like NEPA categorical exclusions, create clearer on- and off-ramps for Section 106 review, and provide an expedited path where no historic properties are present. The draft would also narrow the definition of “undertaking” to exclude state, Tribal, and local permits issued under delegated federal authority—potentially removing a meaningful category of projects from Section 106 review entirely. Program alternatives are narrowed as well, dropping underused options (like “standard treatments”) while streamlining the ones that remain. - Other Notable Changes
- Economic impacts and cost considerations would be added to the calculus for avoidance, minimization, and mitigation measures.
- A new “address adverse effects” definition would introduce a term of art for avoidance, minimization, and mitigation measures.
- ACHP May Ask Pointed Questions – Worth Answering
Beyond the standard request for comment, ACHP would pose specific questions that signal where the rule could still move: whether the MOA process should remain available alongside the new MOD; whether public comment should stay optional or be restored as a requirement; whether more (not less) Tribal consultation detail belongs in the regulatory text; and—notably—for data and statistics quantifying how the current process delays projects. Proponents with real timeline and cost data have a genuine chance to influence the final rule on this last point. - Bottom Line for Energy and Mining Projects
If finalized, the draft NPRM would affect projects on federal public lands, projects receiving federal funding such as Department of Energy grants, and projects requiring federal permits such as Army Corps of Engineers Section 404 permits. The upside for project proponents is real: narrower definitions, expanded exemptions, and a decision-maker no longer bound to negotiate an MOA could mean faster, more predictable reviews.
The trade-off is added litigation risk. Narrower “historic property” and “effect” definitions, along with discretionary Tribal and public consultation, may draw legal challenges from Tribes and environmental groups once a final rule is published or as applied to individual projects. Several organizations have already issued statements and advocacy alerts, signaling that they are monitoring developments closely and may be considering legal challenges. A strong administrative record—and continued voluntary engagement with affected Tribes regardless of what the regulations require—remains the best hedge against that risk. Additionally, the draft NPRM indicates that ACHP may request project-level data from commenters, and while the formal 30-day comment window has not started to run, that window will move fast once it does. Accordingly, project proponents should start developing their comments and supporting timeline and cost data now, so they are ready to submit as soon as the draft NPRM is published.
For questions about this legal alert, please contact a member of Davis Graham’s Energy & Mining Group.