Gov. Code, § 31592.2

(a) In any county, earnings of the retirement fund during any year in excess of the total interest credited to contributions and reserves during such year shall remain in the fund as a reserve against deficiencies in interest earnings in other years, losses on investments, and other contingencies, except that, when such surplus exceeds 1 percent of the total assets of the retirement system, the board may transfer all, or any part, of such surplus in excess of 1 percent of the said total assets into county advance reserves for the sole purpose of payment of the cost of the benefits described in this chapter.

(b) Where the board of supervisors has provided for the payment of all, or a portion, of the premiums, dues, or other charges for health benefits, Medicare, or the payment of accrued sick leave at retirement to or for all, or a portion, of officers, employees, and retired employees and their dependents, from the county general fund or other sources, the board of retirement may authorize the payment of all, or a portion, of payments of the benefits described in this subdivision from the county advance reserves. This payment shall comply with the requirements of Section 401 of Title 26 of the United States Code. Payment may be made directly from the county advance reserves for the benefits described in Section 31691.1.