(a) It shall be the duty of the Office of Treasury and Fiscal Services:

(1) To receive and keep safely all moneys which shall from time to time be paid to the treasury of this state, and to pay all warrants legally drawn on the treasury by the Governor and countersigned by the Comptroller General or, in the Comptroller General's absence, by the deputy comptroller general, and to pay all drafts of the President of the Senate and the Speaker of the House of Representatives for sums lawfully due the members and officers of their respective bodies;

(2) To keep good and sufficient accounting records of every sum of money received into, or disbursed from, the state treasury, utilizing an accounting system in conformity with generally accepted accounting principles and approved by the state auditor;

(3) To keep a true and faithful record of all warrants drawn by the Governor on the treasury and all drafts drawn on the treasury by the President of the Senate and the Speaker of the House of Representatives;

(4) To keep a true and faithful record of the accounts with all designated state depositories in which the state's money is deposited, showing the principal amount and the interest earned in each depository;

(5) To keep safely certificates of stock, securities, state bonds, and other evidences of debt and to manage and control the same for the purposes to which they are pledged;

(6) To invest all state and custodial funds, subject to the limitations of subsection (b) of this Code section and Chapter 17 of this title;

(7) To invest all health insurance funds, subject to the limitations of subsection (b) of this Code section and Chapter 17 of this title;

(8) To invest all self-insurance, liability, indemnification, tort claims, workers' compensation, or related funds, subject to the limitations of subsection (b) of this Code section and Chapter 17 of this title; and

(9) To invest all other funds in its possession, subject to the limitations of subsection (b) of this Code section and Chapter 17 of this title.

(b) Pursuant to an investment policy adopted by the State Depository Board, the Office of Treasury and Fiscal Services shall invest funds through the director. The director shall invest all funds with the degree of judgment and care, under circumstances then prevailing, which persons of prudence, discretion, and intelligence exercise in the management of their own affairs, not for speculation, but for investment, considering first the probable safety of their capital and then the probable income to be derived.