40 CFR 35.143: Allotment.

(a) The Administrator allots air pollution control funds under section 105 of the Clean Air Act based on a number of factors, including:

(1) Population;

(2) The extent of actual or potential air pollution problems; and

(3) The financial need of each agency.

(b) The Regional Administrator shall allot to a State not less than one-half of one percent nor more than 10 percent of the annual section 105 grant appropriation.

(c) The Administrator may award funds on a competitive basis.