The revised NSPS, established by the Environmental Protection Agency (EPA) in 1979 in accordance with the 1977 amended Clean Air Act, could make cleaning of steam coal a necessity within this decade at some utilities for which scrubbing will be inadequate. These regulations apply to utility boilers with heat-input rates greater than 250 multiplied by 10**6 Btu/hr and on which construction began after Sept. 18, 1978.