The ruling, issued in Rogers County District Court, keeps the high-stakes case in state hands for now and denies federal lawyers a formal role in a legal fight that has drawn attention from environmental advocates, tribal nations and business groups across northeastern Oklahoma.

Drummond filed suit earlier this year to block the smelter project, arguing that the development poses risks to the community and that state regulators have not adequately scrutinized its impacts. The project's backers say the facility would bring thousands of construction jobs and hundreds of permanent positions to the region, along with a major boost to the local tax base.

The Justice Department's request to appear came as federal officials signaled interest in the case, though the specific grounds for the federal motion were not detailed in the ruling. The judge's denial means the lawsuit will proceed without the federal government as a formal participant, at least at this stage.

The proposed smelter has become a flashpoint in Rogers County, where residents have packed public meetings to voice concerns about air quality, water use and the industrial footprint of a facility planned near the Verdigris River. Local environmental groups have called for rigorous review, while labor unions and economic development officials have urged the project forward.

Drummond, a Republican, has framed the litigation as a matter of protecting Oklahoma communities and ensuring that large industrial projects meet state standards. His office has sought faster discovery in the case, pressing for documents and testimony from project developers and state agencies.

The judge's decision not to allow the federal attorney to join the case leaves the legal challenge in the hands of the attorney general's office and the project's defenders. It is unclear whether the Justice Department will seek another route to participate or appeal the ruling.

A spokesperson for Drummond's office did not immediately respond to a request for comment. The project's developers also could not be reached for comment.

The case is being watched closely beyond Rogers County, as it tests the balance between state authority over industrial siting and federal interests in energy and manufacturing development. A ruling on the merits could set a precedent for how similar projects are reviewed in Oklahoma.

A scheduling hearing in the case is expected in the coming weeks.