Class VI Permitting, CARB Certification, and Monitoring Program
As part of a multi-organization team, Trihydro is supporting permitting efforts and leading baseline environmental monitoring for a carbon capture and sequestration (CCS) project in EPA Region 7.
Working with an ethanol producer, our role included preparing a Class VI underground injection well (UIC) permit application and a California Air Resources Board (CARB) certification package. We developed the surface and shallow monitoring program and are actively conducting monitoring to establish a clear understanding of site conditions before CO₂ storage begins.
Implementing the Testing and Monitoring Program
The monitoring program includes eco-vegetation, soil efflux, soil gas, passive seismic, and groundwater. The eco-vegetation survey, supported by remote sensing, is based on a digital vegetation map verified by field ecologists. Soil efflux measurements from soil collars establish baseline CO₂ flux rates across the project site. Soil gas and groundwater programs combine routine grab samples analyzed in laboratories with continuous sensor data collected remotely. Annual satellite imagery also tracks vegetation changes that could indicate potential CO₂ leakage.
Developing the Class VI UIC Permit Application and CARB Certifications
EPA determined that the project’s initial Class VI UIC permit application was administratively complete, and it is now in the technical review stage. Trihydro completed submission of the California Air Resources Board (CARB) certification packages.
Once the Class VI permit and CARB certifications are approved, monitoring data, combined with CO₂ injection information, will be used to meet multiple regulatory and reporting requirements, including Class VI standards, the Subpart RR monitoring plan, the IRS 45Q tax credit program, and CARB’s low-carbon fuel standard. Trihydro is integrating this data into a secure web-based management system to support long-term tracking and compliance.
