There are authorized to be appropriated to the Secretary for purposes of carrying out this chapter, not to exceed $3,000,000 for the fiscal year ending September 30, 1982, not less than one-half of which shall be for the purpose of making loans under section 3806(b) of this title; not to exceed $5,000,000 for the fiscal year ending September 30, 1983, not less than one-half of which shall be for the purpose of making loans under section 3806(b) of this title; not to exceed $5,000,000 for the fiscal year ending September 30, 1984, not less than one-half of which shall be for the purpose of making loans under section 3806(b) of this title; and such sums as may be necessary for the fiscal years ending September 30, 1985, and September 30, 1986. Any amount appropriated pursuant to this section shall remain available until expended.