City staff reports radionuclide tests at point-of-diversion location nondetectable; river classified as "vulnerable"

At the council meeting, a staff member addressing follow-up from the July 14 town-hall presented last-year sample results for radionuclide contaminants at the planned Columbia River point-of-diversion. "Our results were that they were ND or nondetected here," the staff member said, referring to uranium, radium and gross alpha/beta emitters tested at the diversion location.

The staff member noted the Columbia River has a technical classification of "vulnerable" by the Oregon Health Authority, meaning it is more susceptible to contamination but does not mean contaminants are currently present. He pointed to upstream jurisdictions — Richland and West Richland — whose 2025 water-quality reports show detectable levels in some radionuclide tests (for example, 5 parts per liter reported in those jurisdictions) but at concentrations below the maximum contaminant levels (MCLs); those systems treat for those contaminants. Council asked operational questions about valve switching, use of existing wells as redundancy and potential system decontamination procedures if future samples were detectable.

Council members noted they did not intend to retire current wells; staff said wells would remain available as redundancy and that the city's water management plan prioritizes aquifer storage and recharge. Council asked staff to clarify standard operating procedures and contingency steps if a detection occurs; staff said those SOPs are not yet finalized and will be developed as the project progresses.