WASHINGTON — The Treasury Department’s grid-impact disclosure rulemaking docket received forty-seven substantive comment filings during its first five business days of public availability, the Treasury comment-tracking system showed Tuesday afternoon, with state energy regulators, environmental advocacy groups, and electric utilities joining the four hyperscaler filings that had dominated the opening day.

The substantive comment filings, distributed through the Federal eRulemaking Portal and reviewed by Treasury staff Tuesday afternoon, represent the most active opening week of any Treasury rulemaking comment cycle in the past three years. The substantive volume reflects what Treasury officials characterized in a Tuesday-afternoon background briefing as “broad cross-sector engagement with a rulemaking whose substantive provisions touch directly on operational practices across multiple distinct industries.”

The state-level comment filings provided the principal substantive expansion of the comment record beyond the opening-day hyperscaler filings. Twelve state public utility commissions filed substantive comments during the past three business days, with the filings concentrated in states hosting substantial existing or planned AI compute infrastructure. The California Public Utilities Commission’s filing, which had been previewed in its Friday observer comment, was the most operationally detailed of the state filings and provided substantive technical commentary on the substantive interplay between the federal framework and the state-level Durazo bill currently advancing through the California Senate.

A senior California Public Utilities Commission staff member, contacted Tuesday afternoon, said the commission’s filing had been “designed to support the operational alignment” between the state and federal frameworks rather than to advocate for substantive modifications to either. The staff member noted that the commission’s filing had been prepared in coordination with the state Senate’s Energy, Utilities and Communications Committee staff to ensure substantive consistency between the state and federal positions.

The New York Department of Public Service filed a substantive comment that emphasized the substantive challenges raised by the multi-tenant facility question that had been the principal focus of the hyperscaler filings. The department’s filing noted that several New York data-center facilities operate under multi-tenant arrangements that would, under the proposed rule’s current language, generate disclosure obligations that the affected operators would dispute. The department urged Treasury to provide additional clarification of the multi-tenant treatment through subsequent rulemaking guidance.

The Texas Public Utility Commission’s filing took a substantively more cautious posture than the California or New York filings. The Texas commission’s filing emphasized the substantive importance of preserving state-level regulatory authority over data-center facility operations and urged Treasury to ensure that the federal disclosure framework would not preempt state-level regulatory frameworks that address parallel substantive questions. The Texas position reflects the state’s broader preference for state-level rather than federal regulatory frameworks.

The environmental-advocacy comment filings provided substantive expansion of the comment record on the curtailment-cooperation provisions. The Sierra Club’s national filing, posted Monday afternoon, urged Treasury to substantially strengthen the proposal’s curtailment provisions by removing the principal exemption framework that the hyperscaler filings had argued for expanding. The Sierra Club filing characterized the current exemption framework as “potentially substantially undermining” the curtailment provisions’ substantive policy purpose.

The Natural Resources Defense Council’s substantive filing took a substantively more nuanced position, supporting the substantive curtailment framework while urging Treasury to provide additional substantive transparency around the criteria for the exemption framework’s invocation. The NRDC filing characterized the proposal’s substantive direction as “broadly appropriate” but argued for substantive procedural improvements that would enhance the framework’s substantive accountability.

The electric-utility comment filings, posted Monday and Tuesday, were filed primarily by the major investor-owned utilities operating in regions hosting substantial AI compute infrastructure. The principal utility comments raised substantive operational questions about the interplay between the proposed federal disclosure framework and the existing utility-side load-management processes that have been developed through state-level regulatory frameworks. The utility filings urged Treasury to provide substantive operational guidance on the integration of the two frameworks.

A senior Edison Electric Institute official, contacted Tuesday afternoon for background, said the trade association’s principal substantive concern was the proposal’s curtailment-cooperation framework, which the association’s filing had characterized as “operationally inadequate” given the substantive complexity of the existing load-management processes. The official said the association had been engaged in substantive dialogue with Treasury staff during the comment period’s first week and expected substantive operational adjustments through subsequent regulatory engagement.

The Treasury staff’s substantive response to the comment filings has been measured. A senior Treasury official, in a Tuesday-afternoon background briefing, said the staff was “carefully reviewing” each substantive comment filing and would incorporate substantive operational improvements into the final rule where the substantive considerations warranted modification. The official emphasized that the substantive policy framework’s core elements would be preserved through the final-rule process.

The Federal Energy Regulatory Commission, which would administer the proposed framework’s principal disclosure channel if the rule is finalized, has been actively engaged with the comment filings through the past week. A senior FERC official, contacted Tuesday afternoon, said the commission had been coordinating substantive review with Treasury staff and expected to file a substantive joint-agency response addressing the comment filings’ substantive operational questions during the third week of the comment window.

The Frontier Model Assurance Council, established under the May 8 voluntary disclosure framework, has not yet filed substantive comments on the Treasury proposal but has indicated through its interim director that substantive comments will be filed during the third week of the comment window. The Council’s substantive interest has been characterized as focused on the operational interface between the model-release disclosure framework and the infrastructure-side disclosure framework rather than on substantive content of the latter.

Senator Maggie Hennessey’s office, in a Tuesday-afternoon statement, said the senator’s substantive engagement with the Treasury rulemaking would “continue to be coordinated” with the senator’s substantive work on the Hennessey-Blackburn AI Transparency and Grid Impact Act. The Hennessey-Blackburn bill’s first Senate Commerce Committee markup is scheduled for early June, with the markup expected to incorporate substantive references to the Treasury rulemaking’s substantive provisions.

The Treasury comment window remains open through July 28, with the substantive comment volume expected to substantially increase during the final three weeks of the window as additional substantive parties complete their substantive substantive review of the proposal’s substantive provisions. The final rule is expected to be published before the end of the fourth quarter.