Northern Indiana Public Service Co. v. Porter County Chapter of Izaak Walton League of America, Inc.

Background\n\nA private utility sought a construction permit to build a commercial nuclear power plant on the south shore of Lake Michigan in Porter County, Indiana. An Atomic Energy Commission licensing board and an appeal board approved the permit. Local residents and environmental groups challenged the approval in court, arguing the agency failed to follow its own rules about how close a reactor can be to a population center.\n\nReasoning\n\nThe Court considered whether the agency’s interpretation of its “population center distance” rule was reasonable. A federal appeals court had set aside the permit because it measured distance from the city’s corporate boundary, which was 1.1 miles away, below the agency’s minimum. The Supreme Court held the agency reasonably used the boundary of actual dense population, not mere political lines, and reversed the lower court’s decision.\n\nReal world impact\n\nThe ruling makes it more likely that utilities can rely on agency measurements of population density rather than municipal borders when siting reactors, allowing the approved permit to proceed unless other legal objections prevail. The Court remanded the case for consideration of other challenges, so this decision does not resolve every dispute about the project. The Court also noted it did not rely on a later regulatory revision published by the new Nuclear Regulatory Commission after the appeals court decision.\n\nDissents or concurrances\n\nJustice Douglas agreed with the outcome but warned that agencies should not change rules after a hearing to suit their needs, and he expressed concern about retroactive or ad hoc rule changes that could undermine public safety and fair notice.\n\n