Supreme Court declines to hear case involving St. Louis contamination

[Marlin]

https://www.ans.org/news/2026-05-20/article-8059/supreme-court-declines-to-hear-case-involving-st-louis-contamination/

[News Wire]

The Supreme Court declined to hear an appeal from Cotter Corporation and Commonwealth Edison regarding radioactive contamination claims in St. Louis. This decision leaves in place an 8th Circuit ruling that permits state-law tort claims to proceed against the companies. The litigation involves allegations that exposure to waste near Coldwater Creek caused cancer in the plaintiffs.

The Supreme Court of the United States on Monday declined to hear an appeal from General Atomics subsidiary Cotter Corporation and Commonwealth Edison, an Exelon company, in a case over alleged radioactive contamination in the St. Louis, Mo., area, leaving in place an 8th Circuit Court ruling that allows the plaintiffs' state-law tort claims to...

The denial came in Cotter Corporation, et al. v. Nikki Steiner Mazzocchio, et al., docket no. 24-1001, according to the court's May 18 orders list and docket. The justices did not explain their decision, as is typical in certiorari denials.

The case: The dispute stems from claims by Nikki Steiner Mazzocchio and Angela Steiner Kraus, who allege that exposure to radioactive waste tied to sites near Coldwater Creek caused them to develop cancer. In an October 2024 decision, the U.S. Court of Appeals for the 8th Circuit affirmed a lower court order declining to dismiss their claims against entities that allegedly handled the waste over the years, including Cotter Corp. and Commonwealth Edison, along with DJR Holdings and the St. Louis...

Read the full article at ans.org:
https://www.ans.org/news/2026-05-20/article-8059/supreme-court-declines-to-hear-case-involving-st-louis-contamination/