All moneys of the Authority from whatever source derived shall be paid to the treasurer of the Authority. Said moneys shall be deposited in the first instance by the treasurer in one or more banks or trust companies in one or more special accounts, and each of such special accounts shall be continuously secured by a pledge of direct obligations of the United States of America, or of the Commonwealth, having an aggregate market value, exclusive of accrued interest, at all times at least equal to the balance on deposit in such account. Such securities shall either be deposited with the treasurer, or be held by a trustee or agent satisfactory to the Authority. All banks and trust companies are authorized to give such security for such deposits. The moneys in said accounts shall be paid out on the warrant or other order of the treasurer of the Authority, or of other person or persons as it may authorize, to execute such warrants or orders. The Department of Revenue of the Commonwealth and its legally authorized representatives are hereby authorized and empowered from time to time to examine the accounts and books of the Authority, including its receipts, disbursements, contracts, leases, sinking funds, investments, and any other matters relating to its finances, operation and affairs. In order to reimburse the General Fund appropriation to the Department of Revenue for costs incurred by the Department of Revenue in making such examination or examinations, the Authority shall be billed by the Department of Revenue from time to time, as such examination or examinations are made, upon a cost basis, at such amounts as the Department of Revenue, with approval of the Executive Board, shall determine; and such amounts shall be paid by the Authority to the Department of Revenue, and shall be by it paid into the General Fund of the State Treasury and credited to the General Fund appropriation of the Department of Revenue. All moneys of the Authority, from whatever source derived, except such part thereof as may be required to pay the administrative and other costs of operating the Authority as may be provided for in the resolution authorizing the issuance of the bonds or in the trust indenture, shall be set aside at such regular intervals as may be provided in such resolution or such trust indenture in a sinking fund, which is hereby pledged to, and charged with, the payment of (1) the interest upon such bonds as such interest shall fall due, (2) the principal of the bonds as the same shall fall due, (3) the necessary fiscal agency charges for paying principal and interest, and (4) any premium upon bonds retired by call or purchase, as herein provided. The use and disposition of such sinking fund shall be subject to such regulations as may be provided in the resolution authorizing the issuance of bonds or in the trust indenture, but except as may otherwise be provided in such resolution or trust indenture, such sinking fund shall be a fund for the benefit of all bonds issued hereunder, without distinction or priority of one over another. Subject to the provisions of the resolutions authorizing the issuance of bonds or of the trust indenture, any moneys in such sinking fund in excess of an amount equal to one year's interest on all bonds then outstanding may be applied to the purchase or redemption of bonds. All bonds so purchased or redeemed shall forthwith be cancelled and shall not again be issued.