California Air Resources Board

To the California Air Resources Board,

We thank you for helping establish the institutional architecture for responsible carbon management. The long-term success of SB905 will likely depend on whether California builds systems that are transparent, enforceable, interoperable, scientifically adaptive, and capable of maintaining public legitimacy over multi-decadal timescales while including new and emerging carbon dioxide removal (CDR) approaches.

Our comments are framed around guiding principles and practices proposed in our recent report, the CORE Framework for Carbon Removal. In addition to these comments, we invite CARB to make use of our resources and recommended language and we offer our support in its use and integration.

Central themes of our comments are as follows.
We recommend that CARB support a rigorous level of quality of CDR technologies and projects through clear definitions of permanence, durability, net negativity, and additionality.
We recommend a regulatory architecture that anticipates future incorporation of additional carbon removal pathways while recognizing that pathway-specific requirements may be developed through subsequent rulemakings. The framework should be inclusive of Biomass Carbon Removal and Storage (BiCRS) and Marine Carbon Dioxide Removal (mCDR) solutions.
We recommend that CARB use EPA's UIC Class VI framework as the foundation for geologic storage oversight, while expanding the regulatory framework to address broader climate integrity (e.g., leakage), environmental justice, public health (e.g., beyond drinking water), and future integration of additional carbon removal pathways through subsequent rulemakings.
We note that there are currently no Class VI criteria for Mafic and Ultramafic storage. As the physics of storage of CO2 in mafic and ultramafic reservoirs differs from conventional geologic storage (depleted oil and gas reservoir storage and saline aquifer reservoir storage), CARB should investigate how these regulations could be tailored to the different storage mechanisms and the feasibility of differentiating requirements given existing regulations, e.g., EPA Class VI and CA CCS Protocol.
We recommend that CARB establish clear procedures for incorporating environmental justice, cumulative impacts, public health considerations, and community input into permitting decisions. CARB should retain authority to require project modifications, additional mitigation measures, or denial when projects would create unacceptable environmental or public health burdens for affected communities, or when community engagement processes identify significant concerns that have not been adequately addressed through project design, mitigation measures, or other corrective actions.
We recommend CARB clarify how nature-based carbon removal targets established under other California policies and programs will interact with SB905 implementation, including how different removal pathways will be accounted for, tracked, and reflected in statewide climate goals.
We recommend CARB evaluate how SB905 requirements interact with emerging carbon management frameworks in other states, federal programs, and regional partnerships, and identify opportunities to promote compatible accounting, reporting, monitoring, and verification approaches where appropriate.

For ease of use, our detailed response (attached) is broken into four parts:
Anchoring Concepts: Essential conceptual structure needed for clear regulatory guidance
Open Question Responses: Direct responses to text box notes shared by CARB
Specific Edits for Current Regulatory Text: Suggestions for definitional edits and section by section comments
Interoperability and Future-Proofing: Recommendations that anticipate and enable future climate action by CARB and other actors

Sincerely,
Carbon180