Allows the Administrator to issue federal general permits on a State, regional, nationwide, or defined-area basis for similar types of discharges from similar sources, and creates a notice-and-continuation rule for expiring general permits. If the Administrator decides not to reissue a general permit, a Federal Register notice must be published at least two years before the permit would expire; if no such notice is published, the expired permit’s terms continue until a replacement is issued or until two years after a later notice of a decision not to reissue is published.