Pub. Resources Code, § 3234

(a) (1) Except as otherwise provided in this section, all the well records, including production reports, of any owner or operator that are filed pursuant to this chapter are public records for purposes of the California Public Records Act (Division 10 (commencing with Section 7920.000) of Title 1 of the Government Code).

(2) Those records are public records when filed with the division unless the owner or operator requests, in writing, that the division maintain the well records of onshore exploratory wells or offshore exploratory wells as confidential information. The records of other wells may be maintained as confidential information if, based upon information in a written request of the owner or operator, the supervisor determines there are extenuating circumstances. For onshore wells, the confidential period shall not exceed two years from the cessation of drilling operations as defined in subdivision (e). For offshore wells, the confidential period shall not exceed five years from the cessation of drilling operations as specified in subdivision (e).

(3) Well records maintained as confidential information by the division shall be open to inspection by those persons who are authorized by the owner or operator in writing. Confidential status shall not apply to state officers charged with regulating well operations, the director, or as provided in subdivision (c).

(4) On receipt by the supervisor of a written request documenting extenuating circumstances relating to a particular well, including a well on an expired or terminated lease, the supervisor may extend the period of confidentiality for six months. For onshore wells, the total period of confidentiality, including all extensions, shall not exceed four years from the cessation of drilling operations as specified in subdivision (e), and for offshore wells the total period of confidentiality, including all extensions, shall not exceed seven years from the cessation of drilling operations as specified in subdivision (e), unless the director approves a longer period after a 30-day public notice and comment period. The director shall initiate and conduct a public hearing on receipt of a written complaint.

(b) Notwithstanding the provisions of subdivision (a) regarding the period of confidentiality, the well records for onshore and offshore wells shall become public records when the supervisor is notified that the lease has expired or terminated.

(c) Production reports filed pursuant to Section 3227 shall be open to inspection by the State Board of Equalization or its duly appointed representatives when making a survey pursuant to Section 1815 of the Revenue and Taxation Code or when valuing state-assessed property pursuant to Section 755 of the Revenue and Taxation Code, and by the assessor of the county in which a well referred to in Section 3227 is located.

(d) For the purposes of this section, “well records” does not include either experimental logs and tests or interpretive data not generally available to all operators, as defined by the supervisor by regulation.

(e) The cessation of drilling operations occurs on the date of removal of drilling machinery from the well site.