Montana’s Department of Environmental Quality is seeking public input on how state agencies collect and analyze greenhouse gas emissions during environmental reviews.

The effort comes out of Senate Bill 221, which directed the Department of Environmental Quality to develop new guidance on greenhouse gas emission assessments in a way that prevents industry and development from becoming bogged down in regulation and litigation.

Signed by Republican Gov. Greg Gianforte, SB 221 was carried by Sen. Wylie Galt, R-Martinsdale, and drew bipartisan support from both chambers.

“Our next steps will be to develop that guidance document that will outline exactly how we will do greenhouse gas assessments for fossil fuel activities, as well as what parameters we’ll look at for non-fossil fuel activities,” Sonja Nowakowski, director of DEQ, said when the bill was signed. “These will be very open and transparent processes, and we look forward to engaging with the public and getting everyone’s input as we move forward.”

In 2025, the bill was among a suite of laws the Montana Legislature passed in response to the state Supreme Court’s decision to uphold a youth-led constitutional lawsuit that found the state could not limit analysis of greenhouse gas emissions during the environmental review process.

In a 6-1 decision in Held v. Montana, the Supreme Court affirmed the Lewis and Clark District Court order that Montana’s constitutional guarantee of a “clean and healthful environment” includes a stable climate system.

The ruling was widely panned by Republican officials across Montana. Legislative leaders told the courts to “buckle up” in response to the decision, and brought a number of bills aimed at changing the judicial system as well as addressing the Held decision and reforming the Montana Environmental Policy Act.

“In the Held v. Montana court case, they tried to twist MEPA into something it was never meant to be — a tool to deny permits and block development,” House Speaker Brandon Ler, R-Savage, said at a signing ceremony of legislation in response to Held on May 1. “With the signing of this MEPA reform package, we’re making it clear that Montana’s environmental policy is about reform decision making, not weaponizing and litigation.”

The department published its draft guidance document on Oct. 1 and is now seeking “substantive public comments” through the end of the month.

Agencies will use the document as a framework for gathering and evaluating greenhouse gas emission data and potential impacts to Montana’s environment while conducting environmental assessments and environmental impact statements required by MEPA.

Under SB 221, state agencies must conduct a greenhouse gas assessment for all fossil fuel projects, as well as for projects involving stationary combustion devices, construction and mobile engine operation, and ecological functions.

The draft document defines greenhouse gas emissions as gases such as carbon dioxide, methane, nitrous oxide, and fluorinated gases that are released into the atmosphere.

It also provides for how agencies should calculate emissions from a project based on size and project type, as well as providing both qualitative and quantitative perspectives on the secondary impacts that greenhouse gas emissions would have on the human environment.

Members of the public can view the document and its appendices on the DEQ website, and submit comments via email to [email protected] or addressed to:

Montana Department of Environmental Quality

Attn: Craig Jones

PO Box 200901

Helena, MT 59620-0901

Public comment will also be accepted at three listening sessions held at the end of the month.

October 27, 6 p.m. – 8 p.m.

Billings Hotel and Convention Center

1223 Mullowney Ln, Billings, MT 59101

October 29, 6 p.m. – 8 p.m.

University Center South Ballroom, The University of Montana

32 Campus Dr, Missoula, MT 59812

October 30, 2025 6 p.m. – 8 p.m.

Delta Hotel

2301 Colonial Dr, Helena, MT 59601

All three listening sessions will be streamed on Zoom. To attend the listening sessions via Zoom, visit DEQ’s website for links.