; (B) of which not less than 4 percent shall be allocated to Indian tribes to perform functions that include— (i) addressing subsequent maintenance costs resulting from the installation of wood heaters under this section; and (ii) training qualified installers and technicians; and (C) among different geographic areas and varying population densities. (2) Allocation priority The Administrator shall provide to each State, regional agency, and Indian tribe described in paragraph (1) for a fiscal year an allocation of funds, with priority given to States, regional agencies, and Indian tribes that will use the funds to support projects that— (A) maximize public health benefits; (B) are the most cost-effective; (C) target the replacement of wood heaters that emit the most pollution; (D) include EPA-certified Step 2 wood heaters and other heaters that achieve emission reductions and efficiency improvements beyond the Step 2 emission reductions standards, as described in the Final Rule; (E) target low-income households; (F) encourage the recycling of old wood heaters when replacing those heaters; and (G) serve areas that— (i) receive a disproportionate quantity of air pollution from wood heaters; (ii) have a high percentage of residents that use wood as their primary source of heat; or (iii) are poor air quality areas, including areas identified by the Administrator as— (I) in nonattainment or maintenance of national ambient air quality standards for particulate matter under section 109 of the Clean Air Act ( 42 U.S.C. 7409 )