Tennessee Code Title 4. State Government § 4-31-1203

(a) The department of finance and administration shall establish the Tennessee transportation state infrastructure fund, in the state treasury, under the control of the authority.

(b) For necessary and convenient administration of the fund, the authority shall establish accounts and subaccounts as necessary to meet any applicable federal law requirements or as necessary or desirable in order to implement this part.

(c) All federal funds shall be invested as required by applicable federal law, and all other funds shall be invested pursuant to state law.

(d) All interest and earnings of the fund shall remain a part of the fund.

(e) No part of the fund shall revert to the general fund on any June 30, but shall remain a part of the fund available for expenditure in accordance with this part.