CA Gov't Code Section 25252.6

The board of supervisors may in its discretion establish and determine the amount of, or may by resolution authorize the county auditor to establish and determine the amount of, a revolving cash trust fund for the purpose of eliminating delays which adversely affect the official operation of offices and departments of the county resulting from regular deposits in and withdrawals from a trust fund established for the use of any county officer or department head. The amount of the revolving cash trust fund shall not exceed the amount of the trust fund. The revolving cash trust fund shall be used by the officer or department head for payment of services, expenses, or other charges which are legally payable out of the deposits in the trust fund.