40 CFR §35.145

1. (a)The Regional Administrator may provide air pollution control agencies, as defined in section 302(b) of the Clean Air Act, up to three-fifths of the approved costs of implementing programs for the prevention and control of air pollution or implementing national primary and secondary ambient air quality standards.
2. (b)Revenue collected pursuant to a State's Title V operating permit program may not be used to meet the cost share requirements of section 105.