Sierra Club threatens EPA with suit over late SO2 plans

Sierra Club and two other environmental groups are threatening to sue EPA over its failure to ensure that adequate state plans are in place to ensure attainment of a key federal air quality standard for sulfur dioxide (SO2) for the Detroit and Baltimore metropolitan areas, citing years of delay in implementing the health-protective limit. In a notice of intent to sue sent to the agency May 18, the Center for Biological Diversity, the Center for Environmental Health and Sierra Club...