A Manhattan federal judge has dismissed the bulk of Pennsylvania’s lawsuit accusing oil companies of polluting the state’s groundwater with a harmful gasoline additive.

The ruling, from U.S. District Judge Vernon S. Broderick of the Southern District of New York, found that attorneys for the state government had failed to state a claim against dozens of firms in the case, part of a consolidated and long-running multi-district litigation, which sought damages for cleaning groundwater that had been contaminated by methyl tertiary butyl ether, or MTBE.