Residents press county over suspected well contamination tied to Knife River operations; county urges state testing

Residents from Prineville raised water concerns Wednesday about high levels of metals in private wells and the county’s options for restricting nearby aggregate mining operations licensed to Knife River.

During public comment, Julie Thompson asked when the county could revoke a conditional use permit (CUP) for Knife River activity and said private wells could be at risk for “high levels of manganese and arsenic and alumna” (as stated in her remarks). County staff answered that while a county can initiate revocation of a CUP, current case law and the administrative record make successful revocation difficult without detailed, admissible evidence — and that affected parties can appeal county action to the Land Use Board of Appeals or to circuit court.

County staff urged residents to support and rely on state sampling and regulatory action. A county attorney‑style speaker explained the jurisdictional split: surface‑water and pollution permits are regulated by state agencies (the Department of Environmental Quality and DOGAMI were referenced in public remarks) and the “smoothest path” to an enforceable remedy is state sampling that connects contaminants to operations. The staff speaker warned that a county‑initiated revocation “is most likely that what we try to do gets reversed, after a lot of time and a lot of money spent” without substantial evidence in the administrative record.

Residents pushed back. Julie Thompson asked how many complaints would be required to provide grounds to revoke a CUP and pressed whether the county or the state would provide water testing or notices to private‑well users. County staff said the county lacks the scientists and laboratory authority to perform regulatory testing and urged collaboration with state legislators and DEQ to obtain sampling and enforcement resources. Several residents urged the county to press Dogami and DEQ to pursue more aggressive sampling and to pause new activity where state regulators found concerning results.

State testing funding update: A speaker identified in the transcript as Mr. Zimmerly told the board that funding for the next round of testing had been approved last Friday and that testing would proceed “as quickly as possible.” The transcript does not specify the funding source or a calendar date for the sampling results.

Other neighborhood concerns: Residents reported recent dust control and truck‑track‑out onto public streets near Knife River operations and asked whether a CUP amendment could require wheel‑wash or truck‑cleaning stations. County staff said construction‑era truck wash provisions exist in some circumstances and that staff would follow up with records, Dogami and Knife River to determine whether additional conditions or enforcement are appropriate. One resident asked whether the county could hire independent geologic or mining expertise to monitor compliance; county officials said that is an option the county will explore.

What the county said it will do: staff advised residents to submit public‑records requests for enforcement files (the county said a PDF response would have no direct charge and printing requests would carry standard fees) and to provide photographs and documentation of dust and track‑out. Commissioners and staff said they will continue pushing state agencies for more testing data and promised to review the record and options for code changes to address future aggregate applications.

What was not decided: no formal county order to revoke permits or to impose new conditions on Knife River operations was issued at the meeting. Residents and staff repeatedly characterized the work as ongoing and contingent on further state testing and legal review.