IACI and member Perpetua opposed 2026 groundwater changes on economic/land-use grounds; DEQ later vacated rulemaking

A current regulatory case shows how IACI and an IACI-board member company participate in the same rulemaking to protect regulated-industry interests. DEQ's 2026 Groundwater Quality Rule docket proposed, among other things, aligning Idaho groundwater standards with federal national primary drinking-water standards and considering changes to aquifer categorization; DEQ described the goal as consistent standards protective of human health. On June 16, IACI submitted formal opposition. IACI argued not all groundwater is or should be treated as drinking water, said universal federal drinking-water standards would conflict with Idaho's differentiated groundwater policy, opposed giving local groundwater/source-water protection measures a larger role in aquifer recategorization, and specifically warned that local requirements could prevent or hinder land uses and that the proposed changes would complicate economic development. On June 18, Perpetua Resources Idaho separately opposed the changes; Perpetua's letter identified its Stibnite Gold Project, said blanket drinking-water standards could impose undue burdens on non-potable groundwater uses, opposed automatic incorporation of future federal standards, and opposed the local-protection language and changes affecting definitions relevant to naturally mineralized mining areas. Perpetua's senior external-affairs executive Mckinsey Lyon appears on IACI's current board. The Idaho Mining Association also opposed the changes. DEQ ultimately vacated the rulemaking, saying stakeholder comments raised substantive considerations needing more discussion and leaving existing groundwater protections unchanged. The record does NOT show IACI, Perpetua or mining interests caused DEQ to vacate the rule; other stakeholders also commented, and DEQ expressly cited the timeline and broader substantive issues. Nor is the industry's position inherently contrary to public interest: IACI/Perpetua argue differentiated standards avoid unachievable rules, preserve state process, and still allow stricter protections where beneficial uses require them. The concentrated-interest audit question is nevertheless concrete: the proposed rule's stated public-health objective intersected with explicit IACI/member concerns over land-use restrictions, compliance burdens, mining operations and economic development. Future work should identify which contaminants/areas/member facilities would face changed compliance costs and what public-health risk reduction the proposed standards would have produced.