Cal. PEN § 6303

(a) The director may enter into a contract, with the approval of the Director of General Services, with any county of the state, upon the request of the board of supervisors thereof, wherein the Director of Corrections agrees to furnish confinement, care, treatment, and employment of county prisoners. The county shall reimburse the state for the cost of such services, such cost to be determined by the Director of Finance. Each county auditor shall include in his state settlement report rendered to the Controller in the months of January and June the amounts due under any contract authorized by this section, and the county treasurer, at the time of settlement with the state in such months, shall pay to the State Treasurer upon order of the Controller, the amounts found to be due.

(b) The Department of Corrections shall accept such county prisoner if it believes that the prisoner can be materially benefited by such confinement, care, treatment, and employment, and if adequate facilities to provide such care are available. No such person shall be transported to any facility under the jurisdiction of the Department of Corrections until the director has notified the referring court of the place to which said person is to be transmitted and the time at which he can be received.

(c) The sheriff of the county in which such an order is made placing a misdemeanant in a jail camp pursuant to this chapter, or any other peace officer designated by the court, shall execute an order placing such county prisoner in the jail camp or returning him therefrom to the court. The expense of such sheriff or peace officer incurred in executing such order is a charge upon the county in which the court is situated.