For Operators - Underground Injection Control

​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​Owners and operators of UIC wells and facilities in California are required to abide by certain laws and regulations to obtain a permit to operate injection wells. On April 1, 2019, new mandates took effect.

The Department of Conservation's Geologic Energy Management Division (CalGEM) hosted an informational workshop regarding implementation of the new regulations. This UIC Workshop Presentation highlights those requirements and enhancements of prior regulations. 

UIC Program Requirements

The Memorandum of Agreement ("MOA'') between the State Water Resources Control Board and CalGEM (collectively, the "Parties") documents how the Parties coordinate the administration of the State's UIC program for Class II wells, regulating discharges to land of produced water from oil and gas operations, responding to incidents such as spills, taking enforcement actions and handling other related issues. The procedures in the MOA are intended to provide a coordinated approach resulting in a single permit satisfying the statutory obligations of both parties in regulating the injection of fluids in Class II wells and a single permit in regulating the discharge of produced water from oil and gas operations to land.

Below are copies of two “checklists” that appear as appendix attachments to the “Revised Memorandum ​of Agreement​." CalGEM and the Water Boards use these checklists to coordinate and streamline the collaborative interagency review of materials associated with “Class II” underground injection projects, as discussed in the MOA to which they are attached. Recognizing that interagency functions related to the regulation of Class II underground injection operations are a subject of interest for many operators and other stakeholders, CalGEM shares these freestanding copies of the checklists here for added convenience and transparency. 

  • The Appendix Attachment 2 checklist is designed to facilitate the evaluation of an entire supporting data package for an underground injection project, such as would accompany an initial application for approval of an underground injection project.
  • 2020.4.8_M​OA Checklist

  • ​​​The Appendix Attachment 3 checklist is designed to facilitate a focused evaluation of proposals to associate additional or different wells with an already-approved underground injection project.
  • Non-expansion Checklist_Final_12.08.21

​While these checklists reference many important requirements, they do not necessarily identify all information an operator must provide in connection with approval and ongoing operation of an underground injection project. The requirements for approval and operation of underground injection projects are governed by applicable statutes and regulations, as well as project-specific terms and conditions identified in the Project Approval Letter or other approval documentation for each underground injection project.​

Such additional requirements include (but are not limited to):

  • California Water Boards​  review and concurrence of all injection projects.
  • Documented California Environmental Quality Act (CEQA) compliance, if a proposed project requires a discretionary permit or approval from CalGEM.


In order to streamline the CalGEM well review and data upload process associated with UIC project applications, CalGEM is requesting operators utilize the 'UIC Project Well List' template and upload it with your WellSTAR Application for Injection Approval form. This template utilizes the same format CalGEM uses to complete well reviews and move data into WellSTAR through an internal Electronic Data Deliverable (EDD). A User Guide to populate the template is also available on the WellSTAR Training Page.

Ongoing Requirements

UIC Project Application Status

Project Review Status from California Water Boards ​(PDF)


Aquifer Exemptions Status

Related Information


​ ​