What you can do, and when

Where to send it:[1]

• Email: [email protected]
• Mail: DEQ Engineering Bureau, PO Box 200901, Helena, MT 59620

Name the project in the subject line (“Quantica Big Sky Campus Public Water Well”). The application, the draft categorical exclusion checklist and the programmatic environmental assessment are all linked from DEQ’s comment page. Read the checklist: it is the document your comment is answering.

Points a comment can make, each grounded in the record:

• Ask for a full environmental review. A categorical exclusion is the lightest review DEQ has. The well serves a project whose gas plants DEQ’s own staff expect to need a major air permit and likely an EIS. Ask DEQ to analyze the well as part of that whole project, not as a stand-alone well.[1][12]
• Ask about the brine. If Madison water needs reverse-osmosis treatment, where does the reject brine go, and under what permit? See The Project.
• Ask about the neighbors’ wells. The claim that the Madison and the Eagle aren’t connected comes from the company. Ask DEQ what independent data supports it, and what monitoring would catch it if the claim is wrong.
• Ask about the water right. DEQ says a data center needs a DNRC water right, a change in use, or water from an existing right holder. Ask which one applies here, and whether DNRC has received an application.[2]

Short, specific and civil beats long and heated. Say where you live if you’re in Yellowstone County or rely on a well.

The commissioners’ office: 406-256-2701, P.O. Box 35000, Billings, MT 59107.[3] Agendas are posted on the county’s commissioners page; check the agenda before going, since meeting times and rooms can change.

Worth knowing when you write: the commissioners have already asked the Legislature to amend the Right to Compute Act so it doesn’t limit county zoning or health and safety authority.[8] Asking them what they will do with that authority if they get it back is a fair question.

The PSC decides what NorthWestern’s other customers pay. Its front page lists the proceedings that matter here: the investigation into resource adequacy and data centers, NorthWestern’s large load tariff, the NorthWestern–Black Hills merger, and NorthWestern’s 2026 integrated resource plan.[6]

• Online: in REDDI, choose “Continue as Guest,” then “Submit a Public Comment in a Docket.”
• Email: [email protected]
• Phone: 406-444-6150 or toll-free 800-646-6150
• Mail: 1701 Prospect Ave, PO Box 202601, Helena, MT 59620-2601

The ask that runs through the November 2025 complaint is simple: a separate rate class for data centers that pays its full cost of service, so residential customers don’t.[7]

The Right to Compute Act is state law, and only the Legislature can change it. The next session convenes in January 2027. Find your senator and representative with the Legislature’s lookup.[9] The case for changing it is on Context.

• Ask for a noise study. Request a pre-construction acoustic assessment for the whole campus and the gas generation, with predicted sound levels at the property line and at the nearest homes, day and night.
• Ask about low-frequency sound. Cooling fans and turbines produce a hum that ordinary A-weighted decibel figures understate. Ask whether the study will measure it separately.
• Ask how close the nearest homes are. Request a site plan showing buildings, cooling equipment and generators against the nearest residences and wells.
• Ask what limit applies. Ask which agency, if any, can set or enforce a noise limit here, and what the company has committed to.
• Ask about mitigation. Enclosures, silencers, berms, and where the loudest equipment would sit.

Where to ask: the county commissioners, above, at a Tuesday meeting or by email, now. The formal opening for the gas plants is DEQ’s air quality permit, if and when an application is filed; a noise question belongs in that comment period too. The well comment on November 6 is about water, so keep this one to the project as a whole.