Cal. Pub. Res. Code § 3207

Any individual or blanket indemnity bond issued in compliance with this chapter may be terminated and canceled and the surety be relieved of all obligations thereunder when the well or wells covered by such bond have been properly completed or abandoned or another valid bond has been substituted therefor. Should the person who has filed a blanket bond properly complete or abandon a portion of his wells covered by the bond, the bond may be terminated and canceled and the surety be relieved of all obligations thereunder upon the filing by such person of an individual bond for each well which is still not producing or which he is still engaged in drilling, redrilling, deepening, or permanently altering the casing. Liability as to individual wells that have been completed or drilled and abandoned under a blanket bond may also be terminated.