Concurrently, legislation has been proposed in previous and current Congresses that would require simultaneous reductions of multiple emissions, and the Administration's National Energy Policy recommends the establishment of mandatory reduction targets for emissions of three main  sulfur dioxide, nitrogen oxides, and mercury.
The legislation proposed in Congress is primarily focused on reducing emissions of mercury.
mnli hypothesis: The legislation proposed in Congress is primarily focused on reducing emissions of mercury. premise: Concurrently, legislation has been proposed in previous and current Congresses that would require simultaneous reductions of multiple emissions, and the Administration's National Energy Policy recommends the establishment of mandatory reduction targets for emissions of three main  sulfur dioxide, nitrogen oxides, and mercury.