Cal. Pub. Resources Code § 6925.1
Whenever, as determined by the commission, any operation conducted under a geothermal exploration permit, prospecting permit, or lease pursuant to this article constitutes an unreasonable risk to the health, safety, or welfare of any human being or of pollution or contamination caused in any manner or resulting from such operations, the commission shall order an immediate suspension of any drilling and production operations, except those which are corrective, protective, or mitigative. Such operations shall not be resumed until the commission determines that adequate corrective measures have been taken. The commission may delegate the power to order a cessation of operations to its executive officer. Resumption of operations shall only be permitted by the commission.
Ca. Pub. Res. Code § 6925.1