A coalition of environmental organizations is suing the U.S. EPA today for failing to clean up the air in California’s San Joaquin Valley. Blackened by dust, smoke, and other pollutants, the region’s air is some of the nation’s worst — but neither the state nor federal government has come up with a workable plan to improve it. Under the Clean Air Act, local air districts must submit realistic plans to reduce air pollution to the EPA; failure to do so can result in loss of federal highway funds and a federal takeover of cleanup efforts. But in the San Joaquin Valley, the air district hasn’t taken steps to clean up the air and the EPA hasn’t intervened; now, the California Clean Air Campaign, the Sierra Club, and Medical Advocates for Healthy Air are suing the EPA for failing to police the San Joaquin Valley Air Pollution Control District. Kevin Hall of the local Sierra Club chapter said of the lawsuit, “It just really captures everything that’s gone wrong here. They abandoned us a decade ago.”