States, Activists Claim EPA 'Residual Risk' Method Spurs Weaker Air Rules

State air officials and environmentalists are sparring with EPA over the agency's approach to performing "residual risk" reviews to determine whether it should revise existing air toxics rules for various industry sectors, claiming that the Obama administration's first residual risk reviews signal an approach that leads to insufficiently strict rules. EPA in September proposed residual risk rules for six industry sectors, including chromium electroplating and marine tank vessel loading. The rules assess the remaining health risks caused by emissions from...