Supremes tackle cross state pollution rules
The Supreme Court heard arguments on Tuesday in a knotty environmental case over how to hold states responsible for air pollution that drifts across their borders and causes harm in downwind states.
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Still, the questioning suggested that there may well be five votes to sustain the Environmental Protection Agency regulations at issue. Its certainly hard, Chief Justice John G. Roberts Jr. said of the task of allocating responsibility, but it is what the statute says, and it seems to me that if E.P.A. had taken a different view, it would have been contrary to the statute.
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The regulation at issue, the Cross-State Air Pollution Rule, sometimes called the transport rule, did not apportion reductions by the amount of pollution contributed by each upwind state. Instead, the agency sought to encourage remedial action where it was cheapest.
The appeals court said that this approach violated the Clean Air Acts good neighbor provision by requiring upwind states to reduce their emissions by more than their own significant contribution to downwind pollution
http://www.nytimes.com/2013/12/11/us/justices-hear-arguments-on-cross-state-air-pollution-rules.html?ref=science