OMAHA, Neb. - Union Pacific Railroad Co.'s $25 million settlement with the federal government to resolve liability stemming from contamination at the Omaha Lead Superfund (OLS) site in Nebraska protects the company from a claim for contribution under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) brought by Asarco LLC, a federal judge in Nebraska ruled July 1 (Asarco LLC v. Union Pacific Railroad Company, No. 12CV416, D. Neb.; 2013 U.S. Dist. LEXIS 92037).