The Center for Biological Diversity (CBD) has sent EPA a notice of intent to sue alleging that EPA violated the Clean Water Act (CWA) by failing to respond to a CBD petition and to develop water quality criteria for black carbon. According to the notice letter, EPA’s failure to respond violates the Administrative Procedure Act, and its failure to establish standards for black carbon violates section 304 of the CWA. Under section 505 of the CWA, EPA has 60 days to correct the alleged violations, or CBD can sue in federal court.

The notice letter alleges that black carbon, also known as soot, is formed by incomplete combustion of fossil fuels, biofuels and biomass, and its atmospheric deposition onto the nation’s waters are subject to CWA authority. CBD and other environmental groups have already sued EPA alleging violations of the Clean Air Act for a failure to respond to petitions seeking regulation of black carbon and greenhouse gases for trains, aircraft, marine vessels, and other nonroad vehicles. They allege that reducing black carbon can slow the rate of climate change and address key effects of global warning.