Alabama Code Title 41. State Government § 41-10-506

(a) All proceeds derived from the sale of any bonds, except refunding bonds, sold by the authority, remaining after payment of the expenses of issuance thereof, shall be turned over to the State Treasurer, shall be carried by him in a special account to the credit of the authority, and shall be subject to be drawn on by the authority solely for the purposes of:

The balance of the said proceeds thereafter remaining shall be set aside as additional security for the bonds or shall be used to pay, purchase or redeem bonds as may be provided in the proceedings authorizing their issuance.

(b) All proceeds from the sale of refunding bonds issued by the authority that remain after paying the expenses of their issuance may be used only for the purpose of refunding the principal of and any unpaid and accrued interest on the outstanding bonds of the authority for the refunding of which the refunding bonds are authorized to be issued, together with any premium that may be necessary to be paid in order to redeem or retire such outstanding bonds.