AB 527: California Environmental Quality Act: geothermal exploratory projects: geothermal field development projects: enhanced geothermal system wells.

Official summary

Legislative Counsel’s Digest (official, as of the latest version). Written by nonpartisan legislative staff; reproduced verbatim.

The California Environmental Quality Act (CEQA) requires a lead agency, as defined, to prepare, or cause to be prepared, and certify the completion of an environmental impact report on a project that it proposes to carry out or approve that may have a significant effect on the environment or to adopt a negative declaration if the lead agency finds that the project will not have that effect. CEQA also requires a lead agency to prepare a mitigated negative declaration for a project that may have a significant effect on the environment if revisions in the project would avoid or mitigate that effect and there is no substantial evidence that the project, as revised, would have a significant effect on the environment.

Existing law establishes the Geologic Energy Management Division in the Department of Conservation, under the direction of the State Oil and Gas Supervisor, who is required to supervise the drilling, operation, maintenance, and abandonment of wells so as to permit the owners or operators of those wells to use all methods and practices known to the industry for the purpose of increasing the ultimate recovery of geothermal resources, as provided. Existing law requires the division to be the lead agency for all geothermal exploratory projects for purposes of CEQA, as specified, and authorizes the division to delegate its lead agency responsibility for geothermal exploratory projects to a county that has adopted a geothermal element for its general plan. Existing law also requires the county in which a geothermal project is located to assume the responsibilities of a lead agency for a geothermal exploratory project upon the request of an applicant, as specified. Existing law defines “geothermal exploratory project” in part as a project composed of not more than 6 wells and associated drilling and testing equipment whose chief and original purpose is to evaluate the presence and characteristics of geothermal resources. Existing law requires wells included within a geothermal exploratory project to be located at least one-half mile from geothermal development wells that are capable of producing geothermal resources in commercial quantities. Existing law requires the owner or operator of a well to keep, or to cause to be kept, a careful and accurate log, core record, and history of drilling the well and requires the log to show, among other things, the character and depth of the formation passed through or encountered in the drilling of the well. Upon completion or abandonment of a well, or upon the suspension of operations of a well, existing law requires true copies of the log, core record, and history to be filed with the district deputy of an oil and gas district, as specified.

This bill would expressly include as part of a geothermal exploratory project, among other things, equipment and activities necessary to establish interconnectivity between wells and reservoirs. The bill would exclude certain wells connecting to geothermal reservoirs from the one-half mile limit described above. The bill would require the log for a well that is part of a geothermal exploratory project that is exempt from CEQA, as described below, to include the chemical and physical characteristics of well stimulation fluids. Upon completion or abandonment of a well, or upon the suspension of operations of a well, that is part of a geothermal exploratory project that is exempt from CEQA, as described below, the bill would require a project developer to disclose the composition of fluids used in all relevant hydraulic fracturing operations with the log for a well and would require the project developer to file a copy of the disclosure with the lead agency.

This bill would, until January 1, 2031, exempt from CEQA geothermal exploratory projects that meet specified conditions and for which the county or the Geologic Energy Management Division is the lead agency. The bill would require a project developer to conduct a reconnaissance survey, that includes certain information, and to supply the lead agency with the reconnaissance survey when applying for an exemption from CEQA. The bill would require the lead agency to engage in a scoping consultation with any California Native American tribe that is traditionally and culturally affiliated with the geographic area of the proposed project, as provided. The bill would authorize the lead agency to require the project applicant to file an indemnity bond, as specified, before the lead agency determines that a geothermal exploratory project is exempt from CEQA. The bill would require a geothermal exploratory project that is exempt from CEQA to include full reclamation of the project site, as provided. The bill would require the lead agency, at least 30 days before making a determination to approve a geothermal exploratory project as exempt from CEQA pursuant to this exemption, to post a written notice of the intent to apply the exemption at the project site and to post a written notice of the intent to apply the exemption and the entire project application on its internet website. If the lead agency determines that the project is exempt from CEQA, the bill would require the lead agency to file a notice with the State Clearinghouse in the Office of Land Use and Climate Innovation and with the county clerk of the county in which the project is located, as provided, and to provide a copy of the notice to specified entities. Because the exemption would apply to projects where the county is the lead agency and the county would be required to engage in a scoping consultation and determine if a project qualifies for this exemption, the bill would impose a state-mandated local program.

This bill would require a geothermal field development project located on a site where a geothermal exploratory project was deployed pursuant to the above-described CEQA exemption to use a baseline for CEQA review that reflects the site before the geothermal exploratory project occurred.

Existing law requires the owner or operator of a well to file a written notice of intention to commence drilling with, and prohibits any drilling until approval is given by, the supervisor or district deputy.

Sponsors

Sponsors by party (alphabetical): Democratic 2

“Support” is shown only as formal sponsorship recorded by the legislature. Roll-call votes are available on the official bill page.

Recent official actions

1. January 22, 2026Consideration of Governor's veto stricken from file.
2. October 6, 2025Consideration of Governor's veto pending.
3. October 6, 2025Vetoed by Governor.
4. September 22, 2025Enrolled and presented to the Governor at 3 p.m.
5. September 10, 2025Senate amendments concurred in. To Engrossing and Enrolling. (Ayes 79. Noes 0. Page 3196.).
6. September 9, 2025In Assembly. Concurrence in Senate amendments pending.
7. September 9, 2025Read third time. Passed. Ordered to the Assembly. (Ayes 36. Noes 0. Page 2739.).
8. September 8, 2025Read second time. Ordered to third reading.
9. September 5, 2025Read third time and amended. Ordered to second reading.
10. August 29, 2025Read second time. Ordered to third reading.
11. August 29, 2025From committee: Do pass. (Ayes 7. Noes 0.) (August 29).
12. August 18, 2025In committee: Referred to suspense file.