The U.S. initially sought $25 billion to clean up decades of contamination at dozens of sites. A U.S. bankruptcy judge in New York in December found Kerr-McGee had improperly shifted its environmental liabilities to Tronox and should pay between $5.15 billion and $14.2 billion, plus attorney's fees. Cole said Thursday that the government decided that the $5.15 billion amount was more than enough to cover the damages.